| Canal Zone League | | Balboa, Colon, Cristobal, Diablo Heights |
| Cuban Winter League | | Almendares, Cienfuegos, Havana, Marianao |
| Mexican Pacific Winter League | | |
| Panama Winter League | | C.P.R. Radiomen, Carta Vieja Yankees, Cerveceria Brewers, Chesterfield Smokers |
| Puerto Rican Winter League | | Aguadilla, Caguas, Mayaguez, Ponce, San Juan, Santurce |
| Venezuelan Winter League | | Cerveceria Caracas, Magallanes, Vargas, Venezuela |
| Independent Negro | | Atlanta Black Crackers, Cincinnati Crescents, Greensboro Red Wings, Harlem Globetrotters |
| All-American Girls Professional Baseball League | | Chicago Colleens, Fort Wayne Daisies, Grand Rapids Chicks, Kenosha Comets, Muskegon Lassies, Peoria Redwings, Racine Belles, Rockford Peaches,
South Bend Blue Sox, Springfield Sallies |
| | |
| American Association | AAA | Columbus Red Birds, Indianapolis Indians, Kansas City Blues, Louisville Colonels, Milwaukee Brewers, Minneapolis Millers, St. Paul Saints, Toledo Mud Hens |
| International League | AAA | Baltimore Orioles, Buffalo Bisons, Jersey City Giants, Montreal Royals, Newark Bears, Rochester Red Wings, Syracuse Chiefs, Toronto Maple Leafs |
| Pacific Coast League | AAA | Hollywood Stars, Los Angeles Angels, Oakland Oaks, Portland Beavers, Sacramento Solons, San Diego Padres, San Francisco Seals, Seattle Rainiers |
| | |
| Southern Association | AA | Atlanta Crackers, Birmingham Barons, Chattanooga Lookouts, Little Rock Travelers, Memphis Chickasaws, Mobile Bears, Nashville Volunteers, New Orleans Pelicans |
| Texas League | AA | Beaumont Exporters, Dallas Eagles, Fort Worth Cats, Houston Buffaloes, Oklahoma City Indians, San Antonio Missions, Shreveport Sports, Tulsa Oilers |
| | |
| Central League | A | Dayton Indians, Flint Arrows, Fort Wayne Generals, Grand Rapids Jets, Muskegon Clippers, Saginaw Bears |
| Eastern League | A | Albany Senators, Binghamton Triplets, Elmira Pioneers, Hartford Chiefs, Scranton Red Sox, Utica Blue Sox, Wilkes-Barre Indians, Williamsport Tigers |
| South Atlantic League | A | Augusta Tigers, Charleston Rebels, Columbia Reds, Columbus Cardinals, Greenville Spinners, Jacksonville Tars, Macon Peaches, Savannah Indians |
| Western League | A | Denver Bears, Des Moines Bruins, Lincoln A's, Omaha Cardinals, Pueblo Dodgers, Sioux City Soos |
| | |
| Big State League | B | Austin Pioneers, Gainesville Owls, Greenville Majors, Paris Rockets, Sherman-Denison Twins, Texarkana Bears, Waco Pirates, Wichita Falls Spudders |
| Colonial League | B | Bridgeport Bees, New Brunswick/Kingston Hubs, Port Chester Clippers, Poughkeepsie Chiefs, Stamford Pioneers, Waterbury Timers |
| Illinois-Indiana-Iowa League | B | Danville Dodgers, Davenport Pirates, Decatur Commodores, Evansville Braves, Quincy Gems, Springfield Browns, Terre Haute Phillies, Waterloo White Hawks |
| Interstate League | B | Allentown Cardinals, Hagerstown Owls, Harrisburg Senators, Lancaster Red Roses, Sunbury Reds, Trenton Giants, Wilmington Blue Rocks, York White Roses |
| New England League | B | Fall River Indians, Lynn Red Sox, Manchester Yankees, Nashua Dodgers, Pawtucket Slaters, Portland Pilots, Providence Grays, Springfield Cubs |
| Piedmont League | B | Lynchburg Cardinals, Newport News Dodgers, Norfolk Tars, Portsmouth Cubs, Richmond Colts, Roanoke Red Sox |
| Southeastern League | B | Anniston Rams, Gadsden Pilots, Jackson Senators, Meridian Peps, Montgomery Rebels, Pensacola Fliers, Selma Cloverleafs, Vicksburg Billies |
| Tri-State League | B | Anderson Rebels, Asheville Tourists, Charlotte Hornets, Fayetteville Cubs, Florence Steelers, Knoxville Smokies, Rock Hill Chiefs, Spartanburg Peaches |
| Western International League | B | Bremerton Bluejackets, Salem Senators, Spokane Indians, Tacoma Tigers, Vancouver Capilanos, Victoria Athletics, Wenatchee Chiefs, Yakima Packers |
| | |
| Arizona-Texas League | C | Bisbee-Douglas Miners, El Paso Texans, Globe-Miami Browns, Juarez Indios, Phoenix Senators, Tucson Cowboys |
| Border League | C | Auburn Cayugas, Geneva Robins, Kingston Ponies, Ogdensburg Maples, Ottawa Senators, Watertown Athletics |
| California League | C | Bakersfield Indians, Fresno Cardinals, Modesto Reds, San Jose Red Sox, Santa Barbara Dodgers, Stockton Ports, Ventura Yankees, Visalia Cubs |
| Canadian-American League | C | Amsterdam Rugmakers, Gloversville-Johnstown Glovers, Oneonta Red Sox, Pittsfield Electrics, Quebec Alouettes, Rome Colonels, Schenectady Blue Jays, Trois-Rivieres Royals |
| Carolina League | C | Burlington Bees, Danville Leafs, Durham Bulls, Greensboro Patriots, Martinsville A's, Raleigh Capitals, Reidsville Luckies, Winston-Salem Cardinals |
| Central Association | C | Burlington Indians, Clinton Cubs, Hannibal Pilots, Keokuk Pirates, Moline/Kewanee A's, Rockford Rox |
| Cotton States League | C | Clarksdale Planters, El Dorado Oilers, Greenville Bucks, Greenwood Dodgers, Helena Seaporters, Hot Springs Bathers, Natchez Indians, Pine Bluff Cardinals |
| Florida International League | C | Fort Lauderdale Braves, Havana Cubans, Lakeland Pilots, Miami Beach Flamingos, Miami Tourists, St. Petersburg Saints, Tampa Smokers, West Palm Beach Indians |
| Lone Star League | C | Bryan Bombers, Gladewater Bears, Henderson Oilers, Kilgore Drillers, Longview Texans, Lufkin Foresters, Marshall Tigers, Tyler Trojans |
| Middle Atlantic League | C | Butler Yankees, Erie Sailors, Johnstown Johnnies, New Castle Chiefs, Oil City Refiners, Uniontown Coal Barons, Vandergrift Pioneers, Youngstown Colts |
| Northern League | C | Aberdeen Pheasants, Duluth Dukes, Eau Claire Bears, Fargo-Moorhead Twins, Grand Forks Chiefs, Sioux Falls Canaries, St. Cloud Rox, Superior Blues |
| Pioneer League | C | Billings Mustangs, Boise Pilots, Great Falls Electrics, Idaho Falls Russets, Ogden Reds, Pocatello Cardinals, Salt Lake City Bees, Twin Falls Cowboys |
| Sunset League | C | Anaheim/San Bernardino Valencias, El Centro Imperials, Las Vegas Wranglers, Mexicali Aguilas, Reno Silver Sox, Riverside Rubes |
| West Texas-New Mexico League | C | Abilene Blue Sox, Albuquerque Dukes, Amarillo Gold Sox, Borger Gassers, Clovis Pioneers, Lamesa Lobos, Lubbock Hubbers, Pampa Oilers |
| Western Association | C | Fort Smith Giants, Hutchinson/Springfield Cubs, Joplin Miners, Leavenworth Braves, Muskogee Reds, Salina Blue Jays, St. Joseph Cardinals, Topeka Owls |
| | |
| Alabama State League | D | Andalusia Arrows, Brewton Millers, Dothan Browns, Enterprise Boll Weevils, Geneva Red Birds, Greenville Pirates, Ozark Eagles, Troy Tigers |
| Appalachian League | D | Bluefield Blue-Grays, Bristol Twins, Elizabethton Betsy Cubs, Johnson City Cardinals, Kingsport Cherokees, New River Rebels, Pulaski Counts, Welch Miners |
| Blue Ridge League | D | Galax Leafs, Leaksville-Draper-Spray Triplets/Abingdon, Mount Airy Graniteers, North Wilkesboro Flashers, Radford Rockets, Wytheville Pioneers |
| Coastal Plain League | D | Goldsboro Goldbugs, Greenville Greenies, Kinston Eagles, New Bern Bears, Roanoke Rapids Jays, Rocky Mount Leafs, Tarboro A's, Wilson Tobs |
| Eastern Shore League | D | Cambridge Dodgers, Dover Phillies, Easton Yankees, Federalsburg A's, Milford Red Sox, Rehoboth Beach Pirates, Salisbury Cardinals, Seaford Eagles |
| Evangeline League | D | Abbeville Athletics, Alexandria Aces, Baton Rouge Red Sticks, Hammond Berries, Houma Indians, Lafayette Bulls, New Iberia Pelicans, Thibodaux Giants |
| Far West League | D | Klamath Falls Gems, Marysville Braves, Medford Nuggets, Oroville Red Sox, Pittsburg/Roseville Diamonds, Redding Browns, Santa Rosa Pirates, Willows Cardinals |
| Florida State League | D | Daytona Beach Islanders, DeLand Red Hats, Gainesville G-Men, Leesburg Pirates, Orlando Senators, Palatka Azaleas, Sanford Giants, St. Augustine Saints |
| Georgia State League | D | Baxley Red Sox, Douglas Rebels, Eastman Dodgers, Fitzgerald Pioneers, Sparta Saints, Vidalia-Lyons Twins |
| Georgia-Alabama League | D | Alexander City Millers, Carrollton Hornets, Griffin Pimientos, La Grange Troupers, Newnan Brownies, Opelika Owls, Tallassee Indians, Valley Rebels |
| Georgia-Florida League | D | Albany Cardinals, Americus Phillies, Cordele Indians, Moultrie A's, Tallahassee Pirates, Thomasville Tigers, Valdosta Dodgers, Waycross Bears |
| Illinois State League | D | Belleville Stags, Centralia Cubs, Marion Indians, Mattoon Indians, Mount Vernon Blues, West Frankfort Cardinals |
| Kansas-Oklahoma-Missouri League | D | Bartlesville Pirates, Carthage Cardinals, Chanute Giants, Independence Yankees, Iola Indians, Miami Owls, Pittsburg Browns, Ponca City Dodgers |
| Kentucky-Illinois-Tennessee League | D | Cairo Egyptians, Clarksville Colts, Fulton Chicks, Hopkinsville Hoppers, Madisonville Miners, Mayfield Clothiers, Owensboro Oilers, Union City Greyhounds |
| Longhorn League | D | Ballinger Cats, Big Spring Broncs, Del Rio Cowboys, Midland Indians, Odessa Oilers, San Angelo Colts, Sweetwater Sports, Vernon Dusters |
| Mountain States League | D | Harlan Smokies, Jenkins Cavaliers, Morristown Red Sox, Newport Canners, Oak Ridge/Hazard Bombers, Pennington Gap Miners |
| North Atlantic League | D | Bloomingdale Troopers, Carbondale Pioneers, Lansdale Dukes, Mahanoy City Brewers, Nazareth Barons, Nyack Rocklands, Peekskill Highlanders, Stroudsburg Poconos |
| North Carolina State League | D | Albemarle Rockets, Concord Weavers, Hickory Rebels, High Point-Thomasville Hi-Toms, Lexington A's, Mooresville Moors, Salisbury Pirates, Statesville Owls |
| Ohio-Indiana League | D | Lima Terriers, Marion Cubs, Muncie Reds, Newark Yankees, Portsmouth A's, Richmond Roses, Springfield Giants, Zanesville Dodgers |
| Pennsylvania-Ontario-New York League | D | Batavia Clippers, Bradford Blue Wings, Hamilton Cardinals, Hornell Maple Leafs, Jamestown Falcons, Lockport Reds, Olean Oilers, Wellsville Nitros |
| Sooner State League | D | Ada Herefords, Ardmore Indians, Chickasha Chiefs, Duncan Cementers, Lawton Giants, McAlester Rockets, Pauls Valley Raiders, Seminole Oilers |
| Tobacco State League | D | Clinton Blues, Dunn-Erwin Twins, Lumberton Cubs, Red Springs Red Robins, Sanford Spinners, Smithfield-Selma Leafs, Warsaw Red Sox, Wilmington Pirates |
| Virginia League | D | Blackstone Barristers, Emporia Nationals, Franklin Cubs, Lawrenceville Cardinals, Petersburg Generals, Suffolk Goobers |
| Western Carolina League | D | Forest City Owls, Hendersonville Skylarks, Lenoir Red Sox, Lincolnton Cardinals, Marion Marauders, Morganton Aggies, Newton-Conover Twins, Shelby Farmers |
| Wisconsin State League | D | Appleton Papermakers, Fond du Lac Panthers, Green Bay Bluejays, Janesville Cubs, Oshkosh Giants, Sheboygan Indians, Wausau Lumberjacks, Wisconsin Rapids White Sox |
| | |
| Cuban League | Foreign | |
| Japanese Baseball League | Foreign | Chunichi Dragons, Hankyu Braves, Kinsei Stars, Kyuei Flyers, Nankai Hawks, Osaka Tigers, Taiyo Robins, Yomiuri Giants |
| | |
| Mexican League | Independent | Mexico City Diablos Rojos, Monterrey Industriales, Puebla Angeles, San Luis Potosi Tuneros, Tampico Alijadores, Veracruz Azules |
| Provincial League | Independent | Drummondville Cubs, Farnham Pirates, Granby Red Sox, Sherbrooke Athletics, St. Hyacinthe Saints, St. Jean Braves |
| Quebec Provincial League | Independent | |
| | |
| Negro American League | Negro Majors | Birmingham Black Barons, Chicago American Giants, Cleveland Buckeyes, Indianapolis Clowns, Kansas City Monarchs, Memphis Red Sox |
| Negro National League | Negro Majors | Baltimore Elite Giants, Homestead Grays, New York Black Yankees, New York Cubans, Newark Eagles, Philadelphia Stars |
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