Hioki won his first MMA title in the Canadian promotion TKO Major League MMA, by defeating Mark Hominick for the featherweight belt. Prior to this Hioki had only one loss to Hiroyuki Takaya in Shooto and had a record of 8-1-1. He successfully defended this title twice before participating in the tournament.
Hioki defeated Masanori Kanehara in the semi-final of the tournament but was unable to continue on to the final to fight Michihiro Omigawa due to an injury in his bout with Kanehara. Kanehara replaced Hioki for the final and ended up winning the tournament.
On May 30, 2010 Hioki fought Takeshi Inoue for the Shooto Featherweight Championship and won by a split decision making him the 9th fighter to win it and the 8th Japanese fighter to do so. Hioki had a controversially lost to Antonio Carvalho during his Shooto career.
Sengoku Featherweight Championship
After defeating Jeff Lawson at Sengoku Raiden Championships 14, Hioki received a title shot against then WVR: Sengoku Featherweight Champion Marlon Sandro. The Championship fight was held at World Victory Road Presents: Soul of Fight on December 30, 2010. Hioki defeated Sandro via unanimous decision. Hioki's superior reach and movement allowed him to out land and counter the aggressive Brazilian. Hioki became the third featherweight Champion for Sengoku. Hioki vacated the title on June 25, 2011 after signing with the UFC.
On the same date he vacated the Sengoku Featherweight Championship: June 25, 2011, UFC officials announced that Hioki had signed a multi fight deal with the UFC. He debuted at UFC 137 on October 29, 2011, where he defeated George Roop via split decision. Hioki faced veteran Bart Palaszewski on February 26, 2012 at UFC 144, winning the bout via unanimous decision. Hioki dominated the whole fight taking down Bart Palaszewski several times and applying a variety of submission attempts. Hioki was offered a title shot but turned it down and instead faced Ricardo Lamas on June 22, 2012 at. He lost the fight via unanimous decision. Hioki faced Clay Guida on January 26, 2013 at. Despite landing more strikes than Guida, and consistently looking for submissions after being taken to the ground, Guida was awarded the split decision. Hioki faced Darren Elkins on August 28, 2013 at UFC Fight Night 27. He lost the fight via unanimous decision. Hioki faced Ivan Menjivar on March 1, 2014 at. He won the fight via unanimous decision. Hioki faced Charles Oliveira on June 28, 2014 at UFC Fight Night 43. He lost the fight via submission, with the loss being the first time Hioki has ever been finished in MMA. Hioki faced Dan Hooker on May 10, 2015 at UFC Fight Night 65. He lost the fight by knockout in the second round, marking his first loss by TKO/KO. Subsequently, he was released from the promotion.
