The Guam Flycatcher (Myiagra freycineti) was a species of bird in the Monarchidae family. It was endemic to Guam.

Although common on Guam as recently as the early 1970s, the Flycatcher's population went into a rapid decline due to predation by the brown tree snake, Boiga irregularis, which was introduced to the island in the 1940s. The last sighting of the flycatcher was in 1983.

Given the small size of the island, the complete absence of recent sightings, and the universal presence of the Brown tree snake in the bird's former habitat, the Guam Flycatcher must be considered extinct.