The Abu Dhabi-owned club were English football's biggest spenders in the summer, splashing out heavily on the likes of forwards Raheem Sterling and Kevin De Bruyne and defender Nicolas Otamendi.
"Really I think this squad is complete," Pellegrini told reporters ahead of City's trip to high-flying Watford on Saturday.
"As always I said that we are not going to close the window but we are not really thinking of any special players to bring in," added the Chilean.
City, three points behind leaders Arsenal and Leicester City at the halfway stage of the season, will be without injured captain Vincent Kompany for at least a month while Samir Nasri is also on the absentee list.
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Kompany has missed more than half of the league games this season, playing in nine out of the 19, and hobbled off within 10 minutes of appearing as a second-half substitute against Sunderland last Saturday.
Pellegrini said promoted Watford, ninth in the league and seven points behind City, were doing a great job but his side were in a good position.
"Always the best position is to be top of the table but I think that this is a special season in the Premier League," he said.
"We are three points behind the leaders and I hope we are going to compete strongly with a very good second half of the season."
(Reporting by Alan Baldwin, editing by Tony Jimenez)
