Wilhelm Mayer (5 December 1917 – 4 January 1945) was a German Luftwaffe ace and recipient of the Knight's Cross of the Iron Cross during World War II. The Knight's Cross of the Iron Cross was awarded to recognise extreme battlefield bravery or successful military leadership. On 4 January 1945, Wilhelm Mayer was killed after being ambushed by RAF Spitfires near Emsland, Germany. He was posthumously awarded the Knight's Cross on 12 March 1945. During his career he was credited with 27 aerial victories, all on the Western Front.