Leitch-Smith was recalled from his loan spell in early September and made his debut coming on as a sub in the 3-2 home defeat to Bury. He then joined Curzon Ashton back in March where he scored 7 goals in 10 games for The Blues.
His performances prompted Dario Gradi to offer him a one-year contract at the end of last season.
This season Leitch-Smith has broken into the first team and has made 8 apperances of which 6 off the subs bench with 2 goals in the process making his first senior start in the 5-5 draw against Chesterfield.
AJ told the official site "I am delighted to be offered another year at Crewe and I didn't hesitate to sign it after Dario had spoken with me.
"It is a great chance for me to progress here and gives me that extra bit of security. I am still learning under the coaches here and am just waiting for another chance. I have broken into the first team squad a lot more this season and really enjoyed it, so I just have to keep going.
"I always think I can score goals if I get the chances and it is nice to know that Dario has that faith in me."Leitch-Smith now joins Matt Tootle and Luke Murphy who have both signed extensions at the club. Crewe boss Dario Gradi will be looking to tie up similar deals with Byron Moore, Ashley Westwood and Shaun Miller over the coming days.