Smith suffered a hamstring injury shortly after grabbing Rangers' goal in the 1-1 draw with promotion rivals Nottingham Forest at Loftus Road a fortnight ago.
Boss Neil Warnock has ruled the former Portsmouth wideman out of Saturday's trip to Middlesbrough but says he is not too far away from a return.
"He'll not be ready for Middlesbrough, but he should be okay for the Leicester game next week," said Warnock.
Source: PA
Source: PA