The Danish forward suffered an ankle injury in the 0-0 draw with Wigan and missed the defeats to Newcastle and Barnsley as well as the draw at Derby.
There had been fears he'd be ruled out until after the game with Fulham but there is a chance he could return at Loftus Road on Friday.
Smith said: “Lasse trained with us yesterday and he'll train today so he'll be in contention to be in the squad.
“It'll be a big boost. Lasse had scored and set a few goals up. He's been a loss but he'll be great to have back.”
The 2-0 loss to Barnsley saw Philipp Hofmann returning to the side for the first time since August.
There is a belief that the German doesn't suit the way Brentford play but Smith disagrees with that assessment and he played down talk of him linking up with Hogan on a regular basis.
He added: “It's not that he doesn't fit but we've got a striker in Scott Hogan who is banging goals in. Hoff is working hard in training. He knows we want him to get fitter and he's doing everything he can.
“He and Hogan could work as a partnership. He's not really a target man. He wants the ball into feet and link things.
“We've been working with him in the box because of his height, size and physical presence he can be more troublesome.”