The Hammers are expected to be active in the transfer market this summer, but Pellegrini has hinted that he will limit the changes to "four or five" players.
Pellegrini told the club's official website: "I think West Ham has a very good team. I know all of the players and I saw most of the games that they played last season.
"So I am sure that, with the players we have in this moment in the squad, and bringing maybe another four or five players in, we are going to have a strong team.
"I think that West Ham had a difficult season last season and I hope that next season we are going to play football that will delight the fans."