Reußenköge (Danish: Reussenkog) is a sparsely populated municipality in the district of Nordfriesland, in Schleswig-Holstein, Germany. It is situated directly adjacent the shoreline of the North Sea coast, in a driving distance of in between 15 up to 29 km northwest of the county-capital city of Husum.

The municipality includes a number of six populated polders (German: Koog, plural: Köge), two of which were financed by Count Heinrich XLIII of Reuß-Schleiz-Köstritz and his wife Louise and thus bear the names Louisen-Reußen-Koog (const. 1799) and Reußenkoog (1789). Additional polders are:

• Sophien-Magdalenen-Koog (const. 1742)
• Desmerciereskoog (1767)
• Cecilienkoog (1905)
• Sönke-Nissen-Koog (1926)
• Beltringharder Koog (only unsettled northern part) (1987)

The name of the municipality was created by combining both the first names, meaning literally in English: polders of the Reußes. A further non-residential location within the municipality is the Hamburger Hallig. In former times being a settled part of the island of Alt-Nordstrand, it was split up from the rest by the Burchardi Flood in the year 1634.