William Jessop may refer to:

• William Jessop (died 1734), English lawyer and Member of Parliament
• William Jessop (1745–1814), English civil engineer notable for work on canals and railways
• William E. Jessop, American leader in the Fundamentalist Church of Jesus Christ of Latter-Day Saints
• Willie Jessop, American leader of and spokesperson for the Fundamentalist Church of Jesus Christ of Latter Day Saints
• William J. E. Jessop (1902–1980), Irish academic, medical practitioner and politician
• Willie Jessop (footballer) (1922–1994), English footballer

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