We analysed diet and foraging strategy of migrating Sedge Warblers during spring migration, postfledging movements, and autumn migration on the Courish Spit (SE Baltic coast). In spring beetles, dipterans, including chironomids, true bugs, and spiders were the most common prey. In late summer and autumn these were plum aphids, chironomids, Hymenoptera, beetles, and spiders. Ecological groups most frequently exploited by Sedge Warblers varied between the seasons. Nevertheless, in both seasons birds tried to use the most common prey. Its taxonomic position is of limited if any importance. The seasonal pattern of arthropod communities in species-specific habitats is crucial for the foraging of Sedge Warblers.