A stuntman was killed and six people were injured Monday during second-unit filming on helmer John Woo’s “The Battle of Red Cliff.”

It’s the latest setback to the production schedule on China’s — and Asia’s — most expensive movie of all time, which has been hit by thesp changes and bad weather.

The 23-year-old stuntman was killed when a fire broke out Monday on the set in northern Beijing after a boat rammed into the set of an ancient warship, Phoenix TV reported. The cause of the fire is still being investigated.

Pic has been a long time coming. Shooting mostly wrapped Nov. 30, and Woo was in Hong Kong when the accident happened. The second-unit director was in charge of the set.

With a budget of $80 million, “Cliff” is the most expensive movie ever made in Asia, with funding coming from producers in the region — China’s China Film, CMC Entertainment in Taiwan, Avex in Japan and South Korea’s Showbox.

The production has been dogged by difficulties — heavy rains washed away part of an outdoor set in Hebei in northern China.

Thesp Tony Leung Chiu-wai (“Lust, Caution”) dropped out and was replaced by Takeshi Kaneshiro. Soon afterward, close Woo ally Chow Yun-fat ankled. Two days after Chow left, Leung was back in the lineup as lead actor, replacing Chow. The film, adapted from China’s classic novel “Romance of the Three Kingdoms,” is written as a four-hour film. For Asian territories, the movie is to be split into two parts, with the first to be released in July in China, Hong Kong, Taiwan and Korea and in October in Japan. Auds outside Asia will get a single movie, expected to clock in at 2½ hours, coinciding with the release of the second part in Asia in December this year.