The Shanghai Municipal Police (SMP; Chinese: ) was the police force of the Shanghai Municipal Council which governed the Shanghai International Settlement between 1854 and 1943, when the settlement was retroceded to Chinese control.

Initially composed of Europeans, most of them Britons, the force included Chinese after 1864, and was expanded over the next 90 years to include a Sikh Branch (established 1884), a Japanese contingent (from 1916) and a volunteer part-time special police (from 1918). In 1941, it acquired a Russian Auxiliary Detachment (formerly the Russian Regiment of the Shanghai Volunteer Corps).

The May Thirtieth Movement (simplified Chinese: 五卅运动; traditional Chinese: 五卅運動; pinyin: Wǔsà Yùndòng) was a major labor and anti-imperialist movement during the middle-period of the Republic of China era. It began when the Shanghai Municipal Police opened fire on Chinese protesters in Shanghai's International Settlement on May 30, 1925 (the Shanghai massacre of 1925). The shootings sparked international censure and nationwide anti-foreign demonstrations and riots.