O'Farrell (Irish: Ó Fearghail) is a surname of Irish Gaelic origin. Bearers include:
Barry O'Farrell, Australian politician
Bob O'Farrell, baseball player
Francis Fergus O'Farrell, Irish soldier of the seventeenth century
Frank O'Farrell, former Irish soccer player and manager
Henry O'Farrell, Australian/Irish attempted assassin
Jasper O'Farrell, Irish-American surveyor and politician
John O'Farrell, British author, broadcaster and comedy script writer
Maggie O'Farrell, British novelist
Maureen O'Farrell, British actress
Michael J. O'Farrell, Irish-American Roman Catholic Bishop
Patrick O'Farrell, Australian/Irish Roman Catholic historian
Patrick H. O'Farrell, Inventor of the two dimensional electrophoresis.
Talbot O'Farrell (1878–1952), stage name of an English music hall singer and film actor
As a place name, O'Farell can refer to:
O'Farrell, Texas, town in Cass County, Texas, United States
