Theophilus Martin "Theo" Nicholls (21 August 1894 – 22 July 1977) was an Australian politician.

Born in Wilmington, South Australia, he received a primary education before becoming a wharf labourer.

[1] He was active in a number of labour movement organisations, such as South Australian Trades and Labour Council, and was vice-president of the South Australian Labor Party.

[1] His nephew, Martin Nicholls, was a Labor MP for Bonython 1963–1977.

This article about an Australian Labor Party member of the Senate is a stub.