O'Fallon

O'Fallon may refer to:

People

 * James O'Fallon (bef 1756–1786), Irish Roman Catholic clergyman
 * John O'Fallon (1786–1865), American businessman, philanthropist, and military officer
 * Peter O'Fallon, American television director

Places

 * O'Fallon, Illinois, United States
 * O'Fallon Township, St. Clair County, Illinois, United States
 * O'Fallon, Missouri, United States
 * O'Fallon Park
 * O'Fallon, St. Louis, a neighborhood in the city of St. Louis, Missouri, United States
 * O'Fallon Street (St. Louis)