SMS Wolf (formerly the Hansa freighter Wachtfels) was an armed merchant raider or auxiliary cruiser of the Imperial German Navy in World War I.

She was the fourth ship of the Imperial Navy bearing this name (and is therefore often referred to in Germany as Wolf IV), following two gunboats and another auxiliary cruiser that was decommissioned without seeing action.

After transferring their crews and any valuable supplies (notably coal, but also essential metals of which the German war effort had much need) to the Wolf, she then sank the vessels.

In addition she carried substantial quantities of rubber, copper, zinc, brass, silk, copra, cocoa, and other essential materials taken from her prizes.

The Wolf, without support of any kind, had made the longest voyage of a warship during World War I. Captain Nerger was awarded the highest German decoration, the Pour le Mérite.

In addition, on 6.2.17, the British troopship HMT Tyndareus was badly damaged by one of Wolf's mines off Cape Town and was only saved from sinking by skillful seamanship.

It shows the SMS Wolf's return to Kiel, Captain Nerger being awarded the Pour le Mérite, and various luminaries touring the ship.