Warren Steed Jeffs (born December 3, 1955 San Francisco California) was the president of the Fundamentalist Church of Jesus Christ of Latter Day Saints (FLDS Church) from 2002 to 2007. While president and "Prophet, Seer and Revelator" of the organization, Jeffs wielded considerable religious as well as secular power, in line with the FLDS Church's theocratic principles.

Jeffs gained international notoriety in May 2006 when he was placed on the FBI's Ten Most Wanted List for unlawful flight to avoid prosecution on Utah state charges related to his alleged arrangement of extralegal marriages between his adult male followers and underage girls. He was arrested in August 2006 in Nevada, and agreed to be taken to Utah for trial. In May and July 2007 the State of Arizona charged him with eight additional counts—including sexual conduct with minors and incest—in two separate cases. His trial, which began early in September 2007 in St. George, Utah, lasted less than a month, and on September 25 the verdict was read declaring him guilty of two counts of rape as an accomplice. On November 20, 2007 he was sentenced to imprisonment for 10 years to life and has begun serving his sentence at the Utah State Prison.

Jeffs resigned from the presidency of the FLDS Church on the day he was sentenced. There are also reports that Jeffs admitted his position of prophet in the FLDS Church was a usurpation in a conversation to William E. Jessop, and declared that "Brother William E. Jessop has been the prophet since Father's passing", though Jeffs' attorneys have claimed he misspoke.