Mites, ticks, and fleas were removed from the fur of 110 specimens of Zapus hudsonius (Zimmermann) from Prince Edward Island, coastal New Brunswick, and northern Nova Scotia. The species which were most abundant and the only ones which occurred on these mice throughout the area were Dermacarus newyorkensis, Neotrombicula harperi, Androlaelaps fahrenholzi, and Ixodes muris. Also examined were 47 specimens of Napaeozapus insignis (Miller) from the above provinces plus Gaspé Peninsula, Quebec. Dermacarus newyorkensis and Neotrombicula harperi were the most abundant ectoparasites. Neotrombicula harperi was the only ectoparasite which occurred on N. insignis throughout the region.