Skating to music from Phantom of the Opera, Pang and Tong recovered after the former's fall on a triple toeloop to post a winning total of 189.20 points in their free skate in Calgary.
Pang and Tong, both 26, were coming off a fourth-place finish at the Torino Olympics last month. They also finished fourth at last year's worlds in Moscow on the heels of a bronze-medal showing in 2004 in Dortmund, Germany.
"I'm nervous and feel a little bit surprised," Pang told CBC Sports through an interpreter. "I didn't imagine I would get this result."
China's Qing Pang and Jian Tong perform in the pairs free skate en route to a gold-medal finish. (CP Photo/Paul Chiasson)
Russia's Maria Petrova and Alexei Tikhonov won the bronze medal, scoring a personal-best 123.18 for their long program and 186.22 overall.
Three-time Canadian champions Valerie Marcoux and Craig Buntin, who sat fourth entering Wednesday's event, came fifth in a PB 181.29.
Fellow Canadians Jessica Dube and Bryce Davison were seventh. As a result of the two high finishes, Canada will send a third pair to the 2007 world meet in Tokyo.
Canada's Joannie Rochette performs her routine during the women's qualifying session at the world figure skating championships on Wednesday. (CP Photo/Paul Chiasson)
"It's an awesome day for pairs skating in Canada," Buntin told CBC Sports. "To have a young team coming up (Dube/Davison) and do what they've done this week is incredible."
Earlier on Wednesday, Canadian champion Joannie Rochette of Ile Dupas, Que., was tops in women's qualifying.
Pang and Tong came into Wednesday's skate second to Zhang and Zhang after recording 64.98 points in Monday's short program.
Zhang and Zhang, who are not related, were totally out of sync in their timing on a double Axel-triple toeloop combo in the long program, while Hao Zhang fell on his triple Salchow jump. They scored 125.01 for their free skating and 186.42 overall.
"We were tired, really tired," said Hao Zhang. "This competition was so close after the Olympic Games. Although we were second, we're very happy to see two Chinese couples in first and second."
Five of the last seven pairs managed personal bests before a loud and appreciative gathering of 8,000.
For Marcoux and Buntin, it was their best-ever finish at the worlds and a significant improvement from an 11th-place standing at the recent Olympics in Italy.
"We made the one mistake on the Axel but, overall, it felt good out there," said Marcoux, who had difficulty on her double Axel landing. "The crowd was amazing.
"We got a personal best, so what a great way to finish our season."
Dube and Davison, rookies at the senior level, improved on a 10th-place effort at the Olympics.
The only glaring error on Wednesday was Dube getting around only once on a planned triple Salchow.
"We're really proud of the way we finished our season with two personal bests," Davison said after a PB of 104.32 in the free skate gave them an overall total of 169.72. "I don't think we could ask for more.
"We gained loads of experience this year. With all the injuries we've been through it makes you grow up quickly."
Meanwhile, Yukari Nakano of Japan was runner-up to Rochette, followed by Emily Hughes of the United States in third.
A second 22-skater group was to perform following the pairs event, with the top 15 in each group advancing to Friday's short program.
with files from Canadian Press
