Olympidytes is an extinct genus of Plotopteridae, a family of large, flightless marine bird superficially similar to modern penguins but more closely related to cormorants and gannets.

[1] The first specimen attributed to Olympidites, a partial postcranial skeleton, was collected in 2012 by Bruce Thiel in Late Eocene to Early Oligocene sediments from the Lincoln Creek Formation.

Another specimen attributed to the genus was collected by James L. Goedert in 2012, from Late Eocene or Early Oligocene rocks from the Jansen Creek member of the Makah Formation, in the southwest of the State of Washington.

In 2016, those remains were identified by Goedert and Gerald Mayr as belonging to a new genus and species of plotopterid, which they named Olympidytes thieli, based on the holotype SMF Av 608, the fragmentary skeleton found by Thiel.

While very similar in size and in shape to the type species, the tibiotarsus lacked a deep groove located on the lateral side of the pons supratendineus where the tandon of the fibularis brevis muscle would attach, a distinctive trait of the genus Olympidytes.