William Speer (1822-1904) was an American pioneer Presbyterian missionary and author. He was missionary to the Chinese in Canton (1847-1850), where he helped establish the first Presbytery in Canton, and to the Chinese in California (1852-1857), where he founded the first Chinese Protestant church outside of China and became a strong advocate for the Chinese in California. Later (1865-1876) he served in Pennsylvania as the Secretary of the Presbyterian Board of Education.