William Pettus Hobby (March 26, 1878–June 7, 1964) was the publisher of the Houston Post and the governor of the U.S. state of Texas from 1917 to 1921.

Born in Moscow, Texas, Hobby became a circulation clerk for the Post in 1895 and was promoted to business writer in August 1901. In 1907 he left the Post to become manager and part owner of the Beaumont Enterprise, and he acquired the entire paper shortly thereafter.

Hobby was elected lieutenant governor of Texas in 1914 and after James Edward Ferguson was removed from office in 1917, he became the youngest governor in the history of the state. He returned to the Enterprise after leaving office and was asked in 1924 to take over as the president of the Houston Post.

In 1931 he married Oveta Culp Hobby, who would later become the first Secretary of the Department of Health, Education and Welfare. In August 1955 Hobby became chairman of the board of the Houston Post Company, which also included the radio station, KPRC, and the television station, KPRC-TV, with Mrs. Hobby as president and editor.