"Gyller" spent the early part of the Second World War in the far north of Norway, protecting Norway's neutrality during the Winter War between Finland and the Soviet Union. During her deployment in North Norway she patrolled Norwegian territorial waters and repeatedly had to sink Soviet naval mines that had broken their moorings and drifted into Norwegian waters. During the Winter War all three of the "Sleipner"-class destroyers commissioned at the time (, "Gyller" and ) were deployed to different ports in Finnmark, with "Gyller" based in Kirkenes.