The Arsenal midfielder joined in the session at the team’s World Cup base in Rio de Janeiro with his injured right knee heavily strapped up.
Oxlade-Chamberlain missed the 2-1 loss to Italy on Saturday night after sustaining ligament damage in a pre-tournament friendly against Ecuador in Miami.
The 20-year-old was enjoying an excellent game until the point of his injury and his return to the fold will be a significant boost to manager Roy Hodgson, whose team need to beat Uruguay on Thursday night or risk an exit at the group stages.
There was further good news for Hodgson in the Monday training session, with Daniel Sturridge showing no signs of the knock he suffered in the Italy game.
Captain Steven Gerrard, who was also hurt in Saturday night’s game, did not start the session but did eventually join it.