Humphries, from Calgary, and rookie brakeman Chelsea Valois of Zenon Park, Sask., posted the fastest time in both heats for a winning time of two minutes 3.30 seconds on the La Plagne track in the French Alps.
"I wouldn't have guessed this would happen at the beginning of the year, but I'm not shocked either," said Humphries, the reigning Olympic champion. "I think everyone believes they are capable of something like this, and always hope for it, so I'm very happy we have been able to do it."
Two American sleds completed a North American sweep of the podium.
Jamie Greubel and Emily Azevedo teamed up in the USA 2 sled to win silver in 2:03.57. Elana Meyers drove the USA 1 sled to the bronze medal in 2:03.81 with Katie Eberling on the brakes.
Humphries has only competed at La Plange twice, winning the gold medal at the track last year. Her win Friday was her ninth career World Cup victory, bringing her career medal total to 16.
"I think this track likes me and I like it," Humprhies said. "It is nice to come back to a track and win again. That is very important to me."
Humphries started her streak by winning the last three World Cup events last season, becoming the first Canadian driver to take the overall women's title in the process.
Humphries welcomed rookie Valois to her crew after the season, and the two showed instant chemistry. They won the Canadian championship in Valois' first-ever competitive bobsled race, then went on to win the season opener at Lake Placid.
Humphries made it five wins in a row in Park City, Utah before heading back to Whistler where she matched Germany's Sandra Kiriasis' six-race winning streak during the 2004-'05 and 2005-'06 seasons.
Humphries broke the record with her seventh victory in a row last week in Winterberg, Germany — a track that had previously given her trouble. Despite her undefeated start to the season, Humphries said there is still a lot of work to do before the 2014 Winter Games in Sochi, Russia.
"Chelsea and I know the Americans are still the fastest on the starts, and the Germans are still the best at driving," she said. "We have lots of room to grow, but we are going to continue working hard together so we can achieve our ultimate goal of standing on top of the podium in Sochi."
Jenny Ciochetti of Edmonton and Emily Baadsvik of St. Stephen, N.B., were 12th in 2:05.14.
Earlier in the day, Latvia's Martins Dukurs continued his dominance of the men's skeleton circuit, winning for the fourth time this year in a time of 2:02.00. Russia's Alexander Tretjyakov won silver in 2:02.54, while Tomass Dukurs, Martins' brother, won bronze in 2:02.92.
Eric Neilson, of Kelowna, B.C., was eighth, Jon Montgomery of Russell, Man., was ninth and Calgary's John Fairbairn was 12th.
The World Cup continues Saturday with men's bobsled and women's skeleton.