Kulamagal Radhai () is a 1963 Indian Tamil-language romance film directed and written by A. P. Nagarajan. It is based on the novel Vaazhvu Engey () by Akilan. The film stars Sivaji Ganesan, B. Saroja Devi and Devika. It was released on 7 June 1963.
Radhai is in love with Chandran and they decide to elope and get married. Radhai is persuaded by his sister-in-law, Vanaja, not to run away from home, which makes Chandran feel betrayed.
Kulamagal Radhai directed by A. P. Nagarajan, who also wrote the screenplay, and produced by Spider Films. It is based on the novel Vaazhvu Engey, by Akilan. Cinematography was handled by W. R. Subba Rao, and the editing by K. Durairaj.
The music was composed by K. V. Mahadevan.
Kulamagal Radhai was released on 7 June 1963. In Sport and Pastime, T. M. Ramachandran called the film "above average", praising Nagarajan's direction, the cast performances and the music but criticising Nagarajan for having made compromises to make the film commercially viable. Kanthan of Kalki wrote .