Win at Leicester and Chelsea, who are 10 points clear of Manchester City and Arsenal, can claim the title on Sunday with victory at home to Crystal Palace.
The Foxes will not roll over, though, having won four in a row to climb out of the relegation zone.
"I was surprised with their bad position," Mourinho said.
"For me it's a good team, good players
I played them very early in the season at Stamford Bridge (winning 2-0 in August).
"I could immediately feel the quality of the team.
"I was surprised that they were in a bad position
I'm not surprised they are out of the relegation zone
I will be not surprised when they stay in the division."
Wednesday's match was scheduled after Chelsea reached the Capital One Cup final on March 1 and the game in-hand is valuable for both sides.
"They are playing well, their results are coming," Mourinho added.
"Their situation is very good
For the quality of their team, I think they are going to survive."
One player stands out for Mourinho - the Argentinian Esteban Cambiasso.
"I won the treble with Cambiasso (at Inter Milan in 2010)," the Portuguese added.
"He was fundamental in my golden team
He's one of the players who means a lot to me, and he's been phenomenal for them
I'm very happy for him."
Chelsea will make a late decision over Diego Costa (hamstring) and Oscar (head knock) and are without Loic Remy (calf).
The likes of Dominic Solanke and Ruben Loftus-Cheek were in FA Youth Cup final action on Monday night and may not be available to Mourinho.
There is little room for manoeuvre in team selection.
Mourinho added: "Our squad in this moment, with the injuries we have, is very short and there is no space for a lot of rotation."
Chelsea's preparations are taking place at St George's Park, the Football Association's national centre.
"We stayed there a couple of times and just to sleep," Mourinho added.
"It's the first time we go and we use the training facilities
The place is fantastic and beautiful.
"We go and we go for a good rest and for a good preparation of the match."
Source : PA
Source: PA