In this paper we discuss patterns of ectoparasitism in gray mouse lemurs in northwestern Madagascar. We describe infestation patterns of eight ectoparasites and in doing so we found five previously undescribed ectoparasite species! Patterns of louse infestation in this species are similar to what we see in other mouse lemur species with males harboring more lice than females and peaks in louse infestation occurring around the seasonal mating period. Perhaps because this is when males are exchanging lice as we previously found in brown mouse lemurs (Microcebus rufus)