Pellegrini: Aguero won't be leaving Man City
Aguero has scored 31 goals in 40 matches in all competitions this season, prompting some reports to link him with a switch to Real Madrid or Barcelona.
But Pellegrini has stated his intention to keep hold of a striker he rates as one of the best players on the planet.
"We are not a selling team," he said.
"Sergio is very happy here. I think he is one of the top five players in the world. He's improved."
Aguero was not included in this season's PFA Premier League Team of the Year, with Chelsea's Diego Costa and Harry Kane of Tottenham chosen ahead of the City frontman.
Commenting on Aguero's omission, Pellegrini added: "I don't know the way they choose the PFA team, so I can't talk about it. "All I can say is that Kun must be in every best team."