Norris suffered a thigh muscle injury during Leeds’ 3-3 draw with Blackburn last weekend.
“It’s another blow and I’m really disappointed for him. He’s had a great start to the season,” Leeds boss Neil Warnock told the Yorkshire Evening Post.
“He’ll be looking at three to four weeks so it’s not long-term but we’ve already lost Paul Green and we’ve got Michael Brown struggling with a hamstring strain. We’re looking thin in that area now.”
