'QK' was a British minelaying operation using motor launches and motor gun boats of the Nore Command (6 September 1941/9 June 1943).

Starting with QK.7 and ending with QK.4D, the operation was created as a partial replacement of the 'PW' series, and was designed to hinder and inflict damage on the German coastal traffic, both naval and mercantile, passing the Netherlands and Belgium. Mines were laid on the area of Schoonveldt, Ostend, Blankenberg and the East Scheldt.