"He passed away today morning," said a source from the hospital.
Bobby, whose condition was serious for a long time, died at 7 a.m. He was in coma since April 2010 after suffering a massive stroke while having a dinner at a restaurant.
Juhi, who has been getting rave reviews for playing a negative role with aplomb in her recently released "Gulaab Gang", tweeted: "This is the perfect screenplay...look at how my brother timed it ... He gave me the biggest gift of my lifetime...saw its release... And..."
Film writer Ombar Qureshi condoled Bobby's death.
"Bobby Chawla - always smiling always affable. You will be missed. Heartfelt condolences to Juhi and all the family. Strength be with you."