John Ahern

John Ahern may refer to:


 * John Ahern (footballer) (born 1970), Australian rules footballer
 * John Ahern (politician) (1934–2020), American politician
 * John E. Ahern (1897–1969), Canadian politician
 * John Ahern (bishop) (1911–1997), Irish Roman Catholic bishop
 * John H. Ahern (1903–1961), British railway modeller and photographer