Justice Janaki Amma (1920–2005), popularly known as Justice P. Janaki Amma, is a former judge of the Kerala High Court. She was born in a village in Thrissur district of Kerala. She lived most of her life in Eranakulam. On 30 May 1974 she was appointed as a judge of the Kerala High Court. She is the second woman in India to be a judge of a High Court. She served as a judge until 22 April 1982.
She was active in freedom struggle during the period 1940-44. She joined the Cochin Praja Mandalam, after completing studies and later joined the Indian National Congress. She was the first woman Municipal Chairperson of Travancore-Cochin. She served as chairperson of Ernakulam Municipal Council from April 1953 to March 1956. She left active politics after joining the judicial service.
She started her legal career as a junior advocate to Panampilly Govinda Menon and later on served as district magistrate, district and sessions judge of Kozhikode, Tellicherry and Manjeri prior to her elevation to the High Court.
She was appointed as a judge of the Kerala High Court on 30 May 1974, thus becoming the second woman in India to have occupied that seat. She retired from the Kerala High Court on 22 April 1982.