Kalpana had bagged the National Award for the Best Supporting Actress for her performance in "Thanichalla Njan".
Popular Malayalam film actress Kalpana passed away today, film director Sibi Malayil said.
She is believed to have suffered a cardiac arrest.
The 50-year-old actress had acted in more than 300 films and was in Hyderabad to attend a private function.
She had bagged the National Award for the Best Supporting Actress for her performance in "Thanichalla Njan".
Popular actress Urvashi and Kalaranjini are her siblings.