- Birthday: 17. November 1920
- Birthplace: Pudukkottai, British India
Ramaswamy Ganesan (17 November 1920 – 22 March 2005), better known by his stage name Gemini Ganesan, was an Indian film actor who worked mainly in Tamil cinema. He was nicknamed "Kadhal Mannan" (King of Romance) for the romantic roles he played in films. Ganesan was one among the "three biggest names of Tamil cinema", the other two being M. G. Ramachandran and Sivaji Ganesan. While Sivaji Ganesan excelled in films with drama, and MGR dominated films with fight sequences, Gemini Ganesan held his own with sensitive portrayals of the yearning lover. A recipient of the Padmashree in 1971, he had also won several other prestigious awards such as the "Kalaimamani", "MGR Gold Medal" and "Screen Lifetime Achievement Award". He came from an orthodox Brahmin family, and was one of the few graduates to enter the film industry at that time.
Gemini Ganesan made his debut with Miss Malini in 1947, but was noticed only after his villainous performance in Thai Ullam in 1953. After playing the lead role in Manam Pola Mangalyam (1954), he finally acquired star status. However unlike Sivaji Ganesan or MGR, Gemini Ganesan was not originally a stage performer, and was never involved in politics. Also, he had not won any National Award for his performances in films. In his long film career spanning over five decades, Ganesan acted in more than 200 films mainly in Tamil, and a few in Hindi, Telugu, Malayalam and Kannada. His performances on the screen were enhanced by successful playback singers like A. M. Rajah and P. B. Sreenivas. In spite of his celebrated film career, Ganesan's personal life – particularly his marriage to multiple women over the years, has often been a subject of criticism. He won 2 Filmfare Awards for his entire acting career.