Mannathu Padmanabhan (2 January 1878  – 25 February 1970) was an Indian social reformer and freedom fighter from the south-western state of Kerala.

He began his career as a teacher in 1893 in a Government primary school.He was the former Headmaster of govt up school north mazhuvannoor.After a few years, from 1905 he changed his profession and started practicing law, in the Magistrates Courts.

In 1924-25 the NSS persuaded the Travancore Government to enact the Nair Regulation which broke up the matriarchal joint family providing for paternal and maternal property to be divided among all the children.

[2][5] On 2 January 2022, Nair Service Society celebrated the 145th Mannam Jayanthi at NSS headquarters, Perunna in Changanassery.

[7] He became a member of the Indian National Congress in 1946 and took part in the agitation against Sir C. P. Ramaswamy Iyer's administration in Travancore.

In 1959, he along with Christian Churches led a united opposition against the State Communist Ministry, which became known as the Vimochana Samaram (liberation struggle).