N. Sivaraj (29 September 1892 – 29 September 1964) was an Indian lawyer, politician and Paraiyar activist from the state of Tamil Nadu. He served as a Member of the Lok Sabha for Chengalpattu from 1957 to 1961.
N.Sivaraj was a prominent leader of depressed class federation and he supported the Justice Party. He was mayor in Madras corporation 1945-1946. He was elected to the Madras Legislative Council on a Justice Party ticket in 1926 and served as member till 1937. From 1937 to 1945, N.Sivaraj served as a member of the Imperial Legislature of India. He participated in the 1952, 1957 and 1962 Lok Sabha elections and served as Member of Parliament from 1957 to 1962 representing Chengalpattu constituency.
AISCF was a first all India political party exclusively for the depressed Class founded by Ambedkar in a national convention held at Nagpur during 17–20 July 1942. It was presided by Sivaraj and he was elected as its first President.
When the Republican Party of India was founded in 1957, he was again elected as its first president and continued working to establish the party’s organisation until he died in 1964.