John Monahan

John Monahan may refer to:


 * John Monahan (scientist), Irish-born biochemist and CEO
 * John Monahan (law professor), professor at the University of Virginia Law School
 * John Monahan (RAF officer), English-born Royal Air Force officer
 * F. John Monahan (born 1943), American politician in Massachusetts
 * John P. Monahan (born 1932), United States Marine Corps general