Orion (HSK-1) was an auxiliary cruiser of Nazi Germany's Kriegsmarine which operated as a merchant raider in World War II.

However the overall effect on the war was evaluated as having been rather minor and so only a small program of converting merchant ships into auxiliary cruisers was initiated on 5 September 1939.

The first two ships being requisitioned were the Kurmark (Orion) and the Neumark (German auxiliary cruiser Widder), and conversion started immediately.

One ship, the Norwegian freighter Tropic Sea, was captured without a fight and sent to occupied France as a prize, though she was scuttled in the Bay of Biscay after encountering HMS Truant.

They met on 1 February 1941, and Orion thus became the only German naval ship of World War II to use a Japanese float plane.

Another six months cruising in the Indian Ocean yielded nothing, though she did encounter and capture her final victim, Chaucer, in July 1941, in the South Atlantic when Orion was on her way home.

On her way to Copenhagen on 4 May 1945, after she had picked up the crew of the old battleship Schlesien, Orion was hit by two bombs dropped by aircraft of the Soviet 51st Mine-Torpedo Aviation Regiment off Swinemünde.