Introduction: Glycerides, commonly called “blood worms”, are relatively thin polychaetes that reach considerable sizes. They have been reported for all the seas of the world from the intertidal zone to abyssal depths. Objective: Evidence the presence of two species of Glycera for the littorals of the Mexican Pacific. Methods: An analysis of the glycerides of the Pacific coast of Mexico was carried out, finding two species that were collected, one of shrimp trawl at a depth of 18 meters off Puertecitos, Baja California, as well as by manual sampling in the intertidal zone of Concepción Bay, Baja California Sur in the Gulf of California. For their taxonomic determination, morphological characters of greater relevance for their identification were examined, such as jaws, aileron shape, parapodia, chaetae, and the type of pharyngeal papillae. Results: We diagnosed and schematized Glycera guatemalensis Böggemann & Fiege, 2001 and Glycera sphyrabrancha Schmarda, 1861. Conclusions: Glycera guatemalensis described for Guatemala and Glycera sphyrabrancha described for Jamaica, are recorded for the first time for the Gulf of California.