Karl Meyer

• Karl Meyer (activist), American pacifist, activist, Catholic worker and tax resister
• Karl Meyer (aviator), World War I flying ace
• Karl Meyer (biochemist), German biochemist
• Karl Meyer (businessman), Norwegian businessman, stockbroker and fascist
• Karl E. Meyer, American journalist
• Karl Friedrich Meyer, Swiss-born American pathologist
• Karl Meyer-class seaplane tender, a Second World War-era ship
• Karl Meyer (footballer), Swiss national team footballer