Frank Baker (died 9 March 1878) was an outlaw in Lincoln County, New Mexico during the Wild West era. He was deputized by Sheriff William J. Brady before taking part in the murder of John Tunstall in 1878, and the Lincoln County Regulators were sent to track down Tunstall's murderers. Baker and Buck Morton were captured next to the Rio Peñasco, but they were shot dead during a failed escape attempt in the "Blackwater massacre".