John O'Hanlon

• John O'Hanlon (chess player), Irish chess master
• John O'Hanlon (politician), Irish Farmers' Party/Independent/National Centre Party politician
• John O'Hanlon (Lackaghmore), Sinn Féin party member who was shot dead by British forces
• John O'Hanlon (writer), Irish priest and writer, known for his ''Lives of the Irish Saints''