"My mother passed away at about 5am today due to cardiac arrest. She died peacefully", Randhir Kapoor tweeted.
She is survived by five children - sons Randhir, Rishi and Rajeev and daughters Ritu and Riima.
Amitabh Bachchan and daughter Shweta Bachchan Nanda arrive at Krishna Raj Kapoor bungalow to pay last respects.
According to Randhir Kapoor, the last rites will be performed at Chembur crematorium.
Following the news of her sudden demise, celebrities took to Twitter and shared their condolences. The sudden demise of Raj Kapoor's wife Krishna Raj Kapoor has left the entire industry in shock.
Krishna Raj Kapoor had been a part of several other family photos. An era passes away, #KrishnaRajKapoor.God give you strength, and may the soul rest in peace. "Condolences to the entire Kapoor family".
"Saddened to hear the demise of #KrishnaRajKapoor ji my deepest condolences, May God give huge strength to whole family". Brother Rishi Kapoor was not present as he has gone to the U.S. for treatment. "Om Shanti", Anupam Kher wrote on the microblogging site. We made sure that she had a great time. Sharing her picture in an Instagram post a while ago, Neetu wrote, "She's the one who teaches you the way to live".