Wang Yaping, Zhang Chen and Lei Jiahui all scored twice as the hosts ran away with the game late on, scoring three times in the last four minutes, to begin the six-team round-robin tournament impressively at Jiangning Sports Centre.
China dominated throughout, but struggled to break down their hard-working opponents until Lu Yueyun’s fierce strike in the 34th minute before Lei curled home a brilliant long-range second a minute later.
Thailand, the outsiders who came through qualifying to reach the tournament, tired early in the second half and Wang took advantage with two neat finishes.
Zhang then scored twice either side of a goal from fellow substitute Ji Xinyi before Lei’s second at the death made the scoreline really emphatic.
Victory for Fan Xuewei’s side was the ideal start as they bid for a top-three spot which would book their spot at next year’s FIFA U-17 Women’s World Cup.
China settled quickly and were soon finding plenty of space with Lu was causing problems Thailand and, soon after her snap-shot had rippled the side-netting, she opened the scoring.
She brought the ball down on her chest in the area and, shaking off the attentions of a defender, fired a shot in off the underside of the bar, leaving goalkeeper Kittiya Aryuwong with no chance.
A minute later it was 2-0 thanks to another moment of individual brilliance.
There looked to be little danger when Lei received the ball 25 yards out, but she curled a glorious shot into the top corner.
Kittiya then had to tip a Li effort on to the bar and Wang nodded in the rebound, but it was ruled out for offside.
China started the second half where they left off in the first and Wang added a third in the 52nd minute, running on to a loose ball and, one-on-one with Kittiya, sliding a low left-footed finish into the corner from around the penalty spot.
The hosts’ superior fitness was telling and Wang got her second five minutes later as she guided a bouncing ball past Kittiya.
Wang was replaced by Zhang after an hour, perhaps with Saturday’s match with Australia in mind.
China continued to push for more goals, though, and Liu Yanqiu was denied by a brilliant save from Kittiya, who pushed her powerful shot on to the bar.
Zhang headed in Li Mengwen’s cross from the right in the 70th minute and, with four minutes to go, Ji turned the ball home after Kittiya failed to cut out a cross.
Zhang stabbed home a seventh a minute later before Lei turned in number eight in the 90th minute.