The Walther P38 is a 9 mm pistol that was developed by Walther as the service pistol of the Wehrmacht at the beginning of World War II. It was intended to replace the costly Luger P08, the production of which was scheduled to end in 1942.

The P38 concept was accepted by the German military in 1938 but production of actual prototype ("Test") pistols did not start until late 1939. Walther began manufacture at their plant in Zella-Mehlis and produced three series of "Test" pistols, designated by a "0" prefix to the serial number. The third series satisfied the previous problems and production for the Heer (German Army) began in mid-1940, using Walther's military production identification code "480". After a few thousand pistols the Heer changed all codes from numbers to letters and Walther was given the "ac" code.