It could be the first of many for the Ste-Julie, Que., native, who is a medal favourite in his three other events.
He finished in two minutes 14.985 seconds Monday, edging Han Tianyu of China.
Viktor Ahn earned the bronze, giving Russia its first-ever short-track medal. J.R. Celsi, the 2010 bronze medallist from Federal Way, Wash., finished fourth.
As Hamelin entered the final lap in the lead, his girlfriend and teammate Marianne St-Gelais couldn't control her excitement, racing from her seat to the sidelines to give him a congratulatory hug.
The gold in the 1,500 was a bit of a surprise given it's not the 29-year-old's best event. He finished seventh in Vancouver where he won gold in the 500 and the 5,000-metre relay. He also has a silver from the 2006 Turin Olympics.
He has been virtually unbeatable this season, winning six World Cup races.
Francois Hamelin, Charles' brother, and Michael Gilday of Yellowknife didn't advance to the final. Gilday was disqualified in the semis and Hamelin was second in the B final.
In the women's 500 preliminaries, St-Gelais, from Saint-Felicien, Que., Jessica Hewitt of Kamloops, B.C., and Valerie Maltais of La Baie, Que., all advanced from the heats.
St-Gelais, Hewitt, Maltais and Marie-Eve Drolet of Chicoutimi, Que., also advanced in the women's 3,000-metre relay.