Marc Ménard, 44, drove a white 1993 Pontiac minivan south in mid-December accompanied by his dog, a basset hound named Maya.
He last communicated with friends on March 14, when he said he was returning home and expected to be crossing the Mexican-American border at Nuevo Laredo.
Ménard is a bus driver for the Société de transport de Laval, the city's public transit autority.
His Facebook profile shows he’d been to the country previously, with pictures from 2010 placing him in various areas of Mexico’s Yucatan peninsula.
Nuevo Laredo sits on the border with Texas and is a notoriously dangerous part of Mexico where a number of drug cartels operate.
Last month, Nuevo Laredo’s police chief went missing and two of his brothers were shot dead in the neighbouring state of Nuevo Leon.
Nuevo Laredo, like the notorious city of Juarez farther northwest along the American border, is reputed to be one of the most dangerous cities in the world due to drug-related crime.
According to friends, he was travelling through Matehuala, a city on the border of the state of Nuevo Leon, in search of a veterinarian.
He needed to have his dog cleared for entry back into the United States before continuing on to the border.
Ménard’s family and friends created a Facebook page asking for help in finding him.
Several of his friends are reportedly travelling to Mexico this week in an effort to bring him home.
He has a large tattoo that wraps from the left side of his chest to his back and over his arm. He also has brown eyes, a shaved head and is about 5’9” (1.8 metres) tall. The licence plate on his van is P95EHL-1.