The Panzerjäger I was the first German Panzerjäger to see service in the Second World War. It mounted the Czech 4.7 cm KPÚV vz. 38 anti-tank gun on a converted Panzer I Ausf. B chassis. It was intended to counter heavy French tanks like the Char B1 bis that were beyond the capabilities of the 3.7 cm Pak 36 anti-tank gun and extended the life of the obsolete Panzer I chassis. A total of 202 Panzer I chassis were converted to Panzerjäger I standard in 1940–41, and were employed in the Battle of France, in the North Africa campaign and on the Eastern Front.

Panzerjäger is a term used for an anti-tank vehicle, as well as anti-tank units. The term was first used in the Wehrmacht, and also post-war by the German Federal Republic Bundeswehr. The term Panzerjäger was used in the Bundeswehr as a designation of rank.