Söderarm is the name of a deactivated Swedish lighthouse station and its surrounding small archipelago in the west part of the Sea of Åland.

In 2002, the coastal artillery was formally liquidated at Söderarm, but still some islands are forbidden for the public to visit.

The Swedish Maritime Administration has confirmed that many Russian mines dating from the First World War may still lie on the sea bottom east of the light station, making anchoring or diving there dangerous.

In 1999, a small aerobeacon mounted on a metallic mast replaced the traditional light, which was deactivated and taken away by the Swedish Maritime Administration in the summer of 2007.

Söderam is frequently reported as a weather station in the Swedish Meteorological and Hydrological Institute (SMHI) shipping news.