Police said that concerned over her husband Harikrishna's condition, his wife Sumalatha and daughter Maginiya ended their life by hanging in the room where he was admitted.
The hospital is located in Vadapalani area in the city.
The couple hailed from Andhra Pradesh and Sumalatha and her daughter reportedly took the extreme step after her husband's condition turned critical.
Police rushed to the spot and shifted the bodies to a government hospital for post-mortem.
(With UNI inputs)