Mahlon K. Cowan, KC (May 10, 1863 – October 28, 1917) was a lawyer and political figure in Ontario, Canada.

He represented Essex South in the House of Commons of Canada from 1896 to 1904 as a Liberal.

[1] He was born in Blytheswood, Canada West, the son of Walter Cowan, an Irish immigrant, and Mary Ann Kitchen.

Cowan was educated in Brantford and Collingwood, went on to study law with Arthur Sturgis Hardy and was called to the bar in 1890.

Cowan served as solicitor for the Grand Trunk Railway from 1904 to 1910.