The 22-year-old has had previous loan spells with Wigan Athletic, Wolves, Fulham and, most recently, French side Reims.
Ojo, who has made 13 first-team appearances for Liverpool, joins Steven Davis (Southampton), Jake Hastie (Motherwell), Jordan Jones (Kilmarnock) and Greg Stewart (Birmingham City) at Ibrox ahead of the 2019/20 campaign.
