Information regarding trichodinid ectoparasites on marine fishes of North America is relatively scarce. In this study, 5 ciliate species from the family Trichodinidae were found associated with 8 fish hosts from the rocky intertidal zone of the western coast of the Baja California Peninsula (BCP), Mexico. All of the host-parasite relationships recorded here are new. Furthermore, 3 of the trichodinid species found are recorded for the first time for Mexico. Trichodinids taxa do not show a noticeable distributional gradient along the BCP, which suggests a wide-continuous distribution of the species throughout the study area.