UFC officials announced the fight on Saturday afternoon.
Hioki is 12-1-1 in last last fourteen fights, with the lone loss coming to Michihiro Omigawa. He owns two notable victories over UFC featherweight contender Mark Hominick, and also holds wins over tough contenders Marlon Sandro and Rumina Sato.
Roop has experienced a career resurgence after going to a draw with Leonard Garcia in a thrilling fight last March. He defeated Chan Sung Jung via spectacular head kick before losing to Hominick, but rebounded with a stunning and decisive win over Josh Grispi.