In April 1918 (the seventh year of the Republic of China), he served as the commander of the Eighth Regiment of the Second Division of the Sichuan Army under Liu Xiang.

[注 1] In March 1920 (9th year of the Republic of China), during the Sichuan-Yunnan War, Liu Xiang assigned Wang Zuanxu's regiment to Yang Sen.

During his tenure in South Sichuan Province, he "developed farmland, water conservancy, built roads, improved prisons, and rewarded overseas students."

Wang Zuanxu was appointed commander of the 1st Division and commander-in-chief of the North Road, and launched an attack on Hechuan and Chongqing from Suining.

In late July of the same year, Wang Zuanxu sent a message to the armies of both sides in Suining, advocating a ceasefire to negotiate the situation in Sichuan.

On April 26 of the same year, the Executive Yuan meeting decided to appoint Wang Zuanxu as acting chairman of Sichuan Province.

On April 27, Wang Zuanxu called Chiang Kai-shek and begged to withdraw his appointment as Acting Chairman of Sichuan Province.