Thomas Michael Williamson (1853 – 16 December 1921) was an Australian politician.
He was born in Sydney to typesetter William Williamson and Anna Maria Annesley, and grandson of Michael Williamson who both served as mayors of Redfern. He attended Lyndhurst College, serving as an articled clerk in his uncle's law firm, Williamson & Williamson, and was admitted as a solicitor in 1877. He later became a partner in the firm. On 8 October 1873 he married Annie McNamara, with whom he had seven children.
He was a candidate for the New South Wales Legislative Assembly for the district of Redfern at the 1882 election, winning a seat at the 1885 election. He did not re-contest the seat in 1887. He told a meeting of electors that this was due to medical advice, while a biographical article in the Australian Town and Country Journal attributes his retirement to the pressures of business. He was a Protectionist candidate at 1889 election, missing a seat by less than 100 votes.
He served as an alderman of Redfern from 1882 to 1888 when he was elected Mayor, serving a one year term to February 1889.
