The young defender will be available for the Lions game against Doncaster at the New Den on Saturday.
Charlie, 19, captain of our reserve side, has been on the bench for the first team once this season against Slavia Prague in the UEFA Cup and was in the squad for the Carling Cup tie against Port Vale.
Development coach Clive Allen said: "I think this move will be very good for Charlie.
"He's done really well for us this season in terms of his performances and the next step for him is to show what he can do in the Football League.
"It will be a big test for him physically but I know he will be up for it, in fact, I'm sure he'll relish it. What he has to do is show he can play as well."
Charlie Lee has joined League One side Millwall on a month's loan.