Joseph-Rosaire Thibaudeau (October 1, 1837 – June 16, 1909) was a Quebec businessman and political figure. He was a Liberal member of the Senate of Canada for Rigaud division from 1878 to 1909. He was born at Cap-Santé, Lower Canada in 1837. Thibaudeau operated the Montreal branch of his older brother Isidore's company until 1895. In 1890, he was named sheriff for the city of Montreal. He was also president of the electric company and vice-president of the telephone company. His nephew Alfred Thibaudeau also served in the Canadian senate.