The highly-rated 19-year old was on fire for the U19s last term with 25 goals before going down with a knee injury in April but Neil Lennon and his staff had already seen enough and rewarded him with a three-year deal which Keatings was delighted with.
"It's a great boost for me confidence-wise. It's brilliant to know that I have another three years playing with Celtic, " Keatings told the club's official website.
"Obviously I am going to be out for a wee while but hopefully I'll come back stronger, faster and fitter and get back in the scene playing football, and hopefully playing first-team football.
"Hopefully I can achieve first-team football here and earn another contract that will keep me here longer. I just want to play first-team football and show what I can do."