Ashby Columbus Dunbar (October 15, 1879 – May 5, 1925) was a Negro leagues outfielder for several years before the founding of the first Negro National League.

Dunbar played with many teams, and appears to have spent the most seasons with the Brooklyn Royal Giants.

He bounced from the Paterson Smart Set, and the Mohawk Giants, to the Louisville White Sox, then Chicago Black Sox.

He was picked up for the Winter season by the Indianapolis ABCs by first playing for their Royal Poinciana Hotel team, and stayed to play a regular summer season with the ABCs.

His last known game was for the Pennsylvania Red Caps.