Louis-Trefflé Dorais (March 19, 1835 – January 2, 1907) was a merchant and political figure in Quebec.
He was born in Sainte-Martine, Lower Canada, the son of Léon Dorais and Félicité Lamagdelaine, and was educated there.
He ran unsuccessfully for a seat in the Quebec assembly in 1881, losing to Charles-Édouard Houde.
In 1896, he moved to Montreal; he died there at the age of 71 and was buried in the Notre Dame des Neiges Cemetery.
After his death in 1907, he was entombed at the Notre Dame des Neiges Cemetery in Montreal.