Synthetoceras was named by Stirton (1932). It is the type genus of Synthetoceratinae, Synthetoceratini. It was assigned to Protoceratidae by Stirton (1932), Thurmond and Jones (1981) and Carroll (1988); to Synthetoceratinae by Hulbert and Whitmore (2006); and to Synthetoceratini by Webb (1981), Prothero (1998), Webb et al. (2003) and Prothero and Ludtke (2007).