Hoover was in China during the Boxer Rebellion

After landing in China, Hoover worked with Bewick and the Chinese Engineering and Mining Company to build gold mines close to Tianjin. He had a strong interest in Chinese history but gave up trying to become proficient in the language. He made it known that Chinese laborers were less effective and of a lower race. He offered suggestions to better the situation of Chinese employees, urging an end to the practice of enforcing lengthy servitude contracts and the implementation of merit-based reforms. Shortly after Hoover landed in China, the Boxer Rebellion erupted, detaining the Hoovers and countless other foreigners until the Battle of Tientsin, where a multinational military force routed the Boxer forces.

The director of the Chinese Engineering and Mining Company agreed to form a new Sino-British enterprise with Bewick, Moreing out of concern for the impending collapse of the Chinese government. In late 1901, Hoover joined Bewick, Moreing as an operating partner after establishing effective control over the new Chinese mining firm.

Hoover often traversed the globe as Bewick, Moreing's operational partner, visiting the company's mines in several countries. After one of the partners acknowledged having sold shares in a mine fraudulently, the firm started to experience growing legal and financial problems in December 1902. After the British government established two independent royal commissioners to look into Bewick, Moreing's labor abuses, and financial transactions in Western Australia, more problems emerged in 1904. Hoover started searching for a way out of the partnership when the firm lost a lawsuit, and in the middle of 1908, he sold his interests.