John Irving Rinaker (November 1, 1830 – January 15, 1915) was a U.S. Representative from Illinois and a brigade commander in the Union Army during the American Civil War.

With the outbreak of the Civil War he raised and organized the 122nd Regiment, Illinois Volunteer Infantry, in 1862 and was commissioned as its first colonel on September 4, 1862.

He served in the Western Theater of the American Civil War and commanded a brigade in the XVI Corps of the Army of the Tennessee.

Rinaker served as delegate to the Republican National Conventions in 1876 and 1884 and then was chairman of the Board of Railroad and Warehouse Commissioners of Illinois 1885-1889.

He successfully contested as a Republican the election of Finis E. Downing to the Fifty-fourth Congress and served from June 5, 1896, to March 3, 1897.