William Hennessy may refer to: William Hennessy (violinist), Australian classical violinist William Hennessy (wrestler), American wrestler William John Hennessy, Irish artist William Maunsell Hennessy, Irish official and scholar William C. Hennessy, American civil servant and political figure Bill Hennessy (Kilkenny hurler) (born 1968) Bill Hennessy (Cork hurler) (1882–1954)