Zeus Silk, Connor Bower and winger Mike Adlard have all penned one-year full-time deals with the Black and Whites, with Jordan Lane signing an initial two-year contract.
Forwards Ross Osborne and Masi Matongo have signed two-year extensions, and hooker Jez Litten has put pen to paper on a three-year deal with the club.
Hull-born Wray, who has spent the last few years in the Rhinos academy, also links up with FC on a three-year contract with the first-team.
Osborne was promoted to the senior squad for pre-season in 2016, and he spent part of the year on loan at Kingstone Press League 1 side York City Knights.
Bower, Silk and Adlard have also caught the eye in the reserves competition, and the latter was awarded the 2016 Hull FC Reserves Team Player of the Year having chalked up plenty of tries for the City of Hull Academy and the reserves this year.
On the new contracts, Hull FC head coach Lee Radford said: “It’s great news for all these blokes extending their contracts with the club. As a coaching staff, we’ve identified there’s some real promise amongst them.
“We’re disappointed with the governing body not formalising an official reserve team competition, but as a club we will strive to make sure we organise as many fixtures for this group as we possibly can.
“I think the challenge for this group of young players is not just to showcase their abilities when playing, but also being as competitive as they possibly can every day at training.
“They have some fantastic players in front of them, and there’s a real challenge to surpass some of these squad members moving forward.
“Their desire to do that will be judged daily throughout the season.”