The UFC card will take place at Bankers Life Fieldhouse.
Hioki (26-6-2) was considered a potential threat to defending champion Jose Aldo when he signed with the UFC in 2011. The Japanese veteran posted wins in his first two Octagon appearances, outpointing George Roop and Bart Palaszewski.
Elkins (16-3) looks to rebound from a first-round knockout loss to Chad Mendes at a UFC event in April. Prior to the loss, Elkins had earned five consecutive wins at 145 pounds.