"West Ham fans want a reaction. We know this team and they will want to show their qualities at home," Puel told reporters.
"When a new manager arrives, there is always a possibility for different players to show their qualities and try and win their place.
"It will be a strong game against them and we have to keep our focus because it will be a crucial game for us."
Leicester, who are 12th in the league, suffered a 2-0 home defeat by Manchester City last Saturday to end a six-match unbeaten run in all competitions. West Ham have gone five league games without a win.
"We are playing a crucial game for us because after losing to Manchester City it is important to bounce back in the Premier League," Puel added.
"It is a new challenge for us because we know the players of West Ham but they have had just one game played under the new manager at Watford.
"They can play with conviction of course but we will see the system and their ambition. The most important thing is to remain focussed with good concentration on our own game."
(Reporting by Aditi Prakash in Bengaluru; Editing by Peter Rutherford)
