S P Sailaja was born to a conservative Saivite family in Konetammapeta in the Nellore district of Andhra Pradesh. She was born to such a household, that was enriched with the musical environment as her father SP Sambamurthy was a well-known proponent of Harikatha and her brother SP Balasubramanyam is a fertile singer in Telugu, Tamil, Kannada,Hindi and Malayalam.

She is married to Subhalekha Sudhakar, a Tollywood Actor. The couple have a son, Sreekar. Apart from yielding songs she has also lended her voice for various artists like Tabu, Sonali Bendre etc. Vasantha Kokila (for Sridevi) (released in 1983); Ninne Pelladatha (for Tabu) (released in 1996); Aavida Maa Aavide (for Tabu) (released in 1998); Murari (for Sonali Bendre) (released in the year 2001) are the films where she has worked as dubbing artist. Sailaja has also acted in a Telugu film directed by K. Viswanath namely Sagara Sangamam. In the film she played the role of a classical dancer which was quite a cakewalk for her,as she is a classical dancer in real life.

As a playback singer she has sung for the films like- Unnai Charanadainthaen (released in the year 2004); Mrugaraaju (released in the year 2001); Aawaragaadu (released in the year 2000); Annamayya (released in the year 1997); Subha Sankalpam (released in the year 1995); Aagraham (released in the year 1993); Siva Shakthi (released in the year 1991); Pelli Pustakam (released in the year 1991); Appula Appa Rao (released in the year 1991); Sutradhaarulu (released in the year 1990); Kokila (released in the year 1989); Raja Chinna Roja (released in the year 1989); Swara Kalpana (released in the year 1989); Bava Marudula Sawal (released in the year 1988); Rudra Veena (released in the year 1988); Swayam Krushi (released in the year 1987); Sri Kanaka Mahalakshmi Recording Dance Troupe (released in the year 1987); Magadheerudu (released in the year 1986); Padamati Sandhya Ragam (released in the year 1986); Sirivennela (released in the year 1986); Thazhuvaatha Kaigal (released in the year 1986); Sur Sangam (released in the year 1985); Jackie (released in the year 1985); Swathi (released in the year 1985); Swathi Muthyam (released in the year 1985); Mayuri (released in the year 1984); Janani Janmabhoomi (released in the year 1984); Rendu Jella Seetha (released in the year 1983); Sagara Sangamam (released in the year 1983); Sitaara (released in the year 1983); Subhalekha (released in the year 1982); Aagaaya Gangai (released in the year 1982); Seethakoka Chilaka (released in the year 1981); Vamsa Vriksham (released in the year 1980); Mosagadu (released in the year 1980); Shankarabharanam (released in the year 1979); Manavoori Pandavulu (released in the year 1978); Pranam Kareedu (released in the year 1978); Sivaranjani (released in the year 1978).