The Ohio–Indiana League was a Class D level minor league baseball league that operated from 1948 to 1951. The league was composed of six teams from Ohio and two teams from Indiana. The Marion Red Sox won three consecutive league championships beginning in 1949. There was also a six–team Ohio–Indiana League that played the 1907 season.

• Bluffton, IN: Bluffton Dregs 1907
• Decatur, IN: Decatur Admirals (Indiana) 1907
• Kokomo, IN - Sharpsville, IN: Kokomo-Sharpsville Combines 1907
• Lima, OH: Lima Terriers 1948; Lima Chiefs 1949; Lima Phillies 1950–1951
• Marion, OH: Marion Cubs 1948; Marion Red Sox 1949–1951
• Muncie, IN: Muncie Reds 1948–1950
• Newark, OH: Newark Yankees 1948–1951
• Portland, IN: Portland Jay Birds 1907
• Portsmouth, OH: Portsmouth A's 1948–1950
• Richmond, IN: Richmond Quakers 1907; Richmond Roses 1948; Richmond Tigers 1949–1951
• Springfield, OH: Springfield Giants 1948–1951
• Van Wert, OH: Van Wert Buckeyes 1907
• Zanesville, OH: Zanesville Dodgers 1948; Zanesville Indians 1949–1950

1907 Ohio–Indiana League

No playoffs held ^[1]

1948 Ohio–Indiana League

Playoffs - Zanesville Dodgers 4 games Springfield Giants 0; Playoffs - Muncie Packers 4 games Portsmouth A's 0
Finals - Zanesville Dodgers 4 games Muncie Packers 2^[2]

1949 Ohio–Indiana League

Playoffs - Marion Red Sox 3 games Portsmouth A's 1; Playoffs - Muncie Reds 3 games Springfield Giants 1
Finals - Marion Red Sox 4 games Muncie Reds 3^[3]

1950 Ohio–Indiana League

Playoffs - Marion Red Sox 3 games Springfield Giants 1;Playoffs - Newark Yankees 3 games Richmond Tigers 2
Finals - Marion Red Sox 4 games Newark Yankees 0 ^[4]

1951 Ohio–Indiana League

Newark won the first half which ended June 18. Newark folded July 17 and the second half was started over, won by Marion. The Springfield Giants were a playoff qualifier.

Playoffs - Marion Red Sox 4 games Springfield Giants 0^[5]

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