Aamir, who played an alien in the satirical comedy, turned up in a Chinese-style tunic and pants much to the amusement of the guests.
The 50-year-old actor's family, including wife Kiran Rao, ex-wife, Reena, daughter Ira and nephew Imran Khan also attended the success party.
Big B, who will be next seen in PK producer Vidhu Vinod Chopra's upcoming film Wazir, also attended the bash. He later posted pictures of the party on Facebook and wrote: "At the celebration party for PK, and the joy of seeing the joys of others. Vinod, Raju and the wonderful Anushka."
Also in attendance were Kangana Ranaut, Deepika Padukone, Ranveer Singh, Anil Kapoor, lyricist Javed Akhtar, Zoya Akhtar, director Imtiaz Ali, Sharman Joshi, Jackie Shroff, Tabu, Boman Irani, Aditi Rao Hydari, Sanjay Dutt's wife Maanyata, Sushant Singh Rajput and his girlfriend Ankita Lokhande, Congress leader Priya Dutt and UTV Disney's Siddharth Roy Kapur.
PK became the first Indian film to touch the three-figure mark in the largely restrictive Chinese movie market.