Jayanthi's father Balasubramanyam worked as English professor at the St Joseph's College in Bangalore. Her mother was Santhanalakshmi. Jayanthi was the eldest of three siblings and had two younger brothers. As a child, Jayanthi went to the studios to see her idol N T Rama Rao. He called her and made her sit on his lap. Affectionately he had asked her whether she would agree to become his heroine and the little girl had merely blushed. The pair would go on later in life to produce successful films such as Jagadeka Veeruni Katha, Kula Gowravam, Kondaveeti Simham and Justice Chowdhury. Jayanthi has paired with actor Rajkumar in a record 45 numbers of films. This is the highest ever number of films which Rajkumar has ever paired with any actress. Her life changed completely when noted Kannada director Y R Swamy spotted her during one of her dance rehearsals. He brought her to Kannada films such as Jenu Goodu. He also changed her name to Jayanthi. Jeenu Goodu was Jayanthi's first Kannada film. She was married to Film Director Peketi Sivaram. He backed her all the way and very soon she became a famous actress in Kannada. She acted alongside veterans like Dr.KS Ashwath and Pandari Bai. Incidentally this was actress Chandrakala's first film as well. Jenu Goodu was a commercial success. Her next major film was T V Singh Thakur's Chandavalliya Thota. The film starred veteran actors Udaya Kumar, Dr.Rajkumar and Jayashree. This was the first film that paired Raj and Jayanthi. Based on Ta Ra Su's novel by the same name, Chandavalliya Thota was a huge success and even won the President's Medal for best film. The next major film that Jayanthi starred in was Miss Leelavathi. The film was a huge success and catapulted Jayanthi to fame. She is credited for introducing most of the modern day outfits onto the Kannada screen for the first time. Miss Leelavathi had some of the lovely songs like "Nodu ba nodu ba nammoora" and Kuvempu's classic "Doni Saagali". Miss Leelavathi got Jayanthi the President's award. Jayanthi fondly remembered the occasion in one of her interviews when she received the award from Smt Indira Gandhi (then IB Minister). She has also acted in numerous films with Kalyan kumar. In Tamil She acted with all major stars. She was director K. Balachander's most sought after actress and they went on to work in numerous films. In 2009, she gave her voice to an HIV/AIDS education animated software tutorial created by the nonprofit organization Teach AIDS.