Nandamuri Harikrishna, 61, succumbed minutes after he was brought with critical injuries.
Andhra Pradesh Chief Minister N. Chandrababu Naidu and other members of the NTR family rushed to Telangana's Nalgonda district, where NTR's son Nandamuri Harikrishna died in a road accident early on Wednesday.
Shocked family members reached Kamineni Hospital at Narketpally, where Mr Harikrishna, 61, succumbed minutes after he was brought with critical injuries.
Mr Harikrishna's sons Junior NTR and Kalyam Ram, both actors, were the first to reach the hospital and broke down on seeing the body of their father.
His brother-in-law N. Chandrababu Naidu along with his son Nara Lokesh flew in a helicopter from Vijayawada.
"Beginning as a child artist, Harikrishna donned many roles in Telugu movies and endeared himself to people. As a political leader too, he rendered commendable services. His tragic death is a deep loss to the TDP and the state," the Chief Minister said in a statement.
Leader of opposition in the Assembly Y S Jaganmohan Reddy also condoled the former minister's death. "Shocked at the sudden demise of Nandamuri Harikrishna. My thoughts and prayers are with the bereaved family members," Mr Reddy said in a tweet.
Mr Harikrishna's brother actor Balakrishna, sister and former central minister D. Purandeswari and brother-in-law D. Venkateshwara Rao also reached the hospital. Actor Jagapati Babu was also among those who came to hospital.
Police had a tough time controlling the crowd, which had gathered outside the hospital.
Meanwhile, several relatives, friends, Telugu Desam Party leaders and Telugu film personalities started pouring in at Mr Harikrishna's house in Hyderabad.
Mr Harikrishna's another sister and Naidu's wife Bhuvaneswari and her daughter-in-law Brahmani reached the residence.
Mr Naidu, who is also president of the TDP, expressed his shock over the death of Harikrishna, a member of party's highest decision making body, politburo. He described Harkrishna's death as a huge loss to the family and TDP.
Mr Naidu recalled his services to the film industry and politics. He also recalled that NTR was very fond of him and picked him to drive his Chaitanya Ratham across Andhra Pradesh.
Telangana Chief Minister K. Chandrasekhar Rao expressed grief over Harkrishna's death and conveyed his condolences to the bereaved family.