Liverpool winger Ojo started the Group A match in Jeonju, South Korea, before being withdrawn in the 63rd minute. His clubmate Ovie Ejaria was an unused substitute.
A goal from Lewis Cook early in the second half put the Young Lions on course to follow up their opening-game victory over Argentina with another win, but Fikayo Tomori's own goal saw Guinea claim a share of the spoils.
England's final group-stage fixture sees them take on the host nation on Friday.