The Chilean has already added Fernandinho, Stevan Jovetic, Alvaro Negredo and Jesus Navas to his squad, as City look to win back the Premier League title from Manchester United.
However, the former Malaga boss is not finished in the transfer market yet.
"The club has spent money on important players, like Stevan and Negredo," said Pellegrini.
"But we must remind you that last year there was (Mario) Balotelli and (Carlos) Tevez, so we had to replace two very good players with another two very good players.
"So, we have the month of July and some days of August to finish the squad completely. It's not absolutely complete, but it's very near to being complete."
Yaya Toure believes the club's new signings will provide a boost as they look to bounce back from a disappointing season.
Under former boss Roberto Mancini, City lost in the FA Cup final and bowed out of the UEFA Champions League in the group stage without winning a game.
However, the Ivorian is pleased with the new additions to the side, and hopes they will be part of a successful campaign next term.
"It’s very good to see," he said.
"They’re unbelievable players. They play with their national teams – Negredo, Navas and Fernandinho - and Jovetic is a great young talent, he’s got a fantastic future ahead of him.
"I’m glad all these players have come to the club because we need it and hope this season is going to be fine for us."
