Sishtla Sreeramamurthy Janaki (born 23 April 1938), popularly known as S. Janaki, is an Indian playback singer, and occasional music-composer hails from Andhra Pradesh. She is one of the best-known playback singers in South India who has recorded 48000 songs in Malayalam, Tamil, Telugu, Kannada, Odiya, Hindi, Bengali, Tulu, Sanskrit, Sinhalese, Badaga, Punjabi, Urdu, Japanese, German, Latin and Arabic languages. Janaki started her career in 1957 and has spanned over six decades. She has recorded songs in more than seventeen regional Indian languages and foreign languages. She has won four National Film Awards and 32 different State Film Awards. Her association with singer S. P. Balasubrahmanyam and composer Ilaiyaraaja is well known. In the 60s and 70s, her duets with P.B.Srinivas were some of the most romantic duets in the history of Tamil film music.
S. Janaki, who is known as "The Nightingale of the South", is a recipient of an honorary doctorate from the University of Mysore and the Kalaimamani award from Tamil Nadu State Government. S.Janaki is called the Queen of Expressions for her ability to express different kind of emotions.
In 2013, she refused the offer of a Padma Bhushan award by the Government of India, saying that it had come "too late" and that South Indian artists were not given their due recognition.
A book titled, 'Aalpanathile Thenum Vayambum', authored by Abhilash Pudukad and published by Logos Books details the singing, life and songs of S. Janaki.