In the present survey 18 species of endo and ecto-parasites were recorded during the examination of 50 Mus musculus (Linnaeus, 1758) among 10 localities in Erbil city, of which 7 species were protozoan and as follows : Chilomastix bettencourti (da Fonseca 1915)82%; Giardia muris (Filice, 1952) 68%; Tritrichomonas muris (Grassi,1879)36%; Entamoeba histolytica (Schaudinn,1903) 24%; Entamoeba coli (Grassi,1879)32%; Eimeria sp. 28% and Trypanosoma musculi (Kendall,1906) 2%; and 8 species were helminthes as follows: 4 Cestodes: Rodentolepis nana (von Siebold, 1852) 8%; Hymenolepis diminuta (Rudolphi, 1819)2%; larval stage of Echinococcus granulosus (Batsch, 1786)8%, Cysticercus fasciolaris (Rudolphi, 1808)6%, 4 Nematodes: Aspiculuris tetraptera (Nitzsch, 1821)8%; Syphacia obvelata (Rudolphi, 1802)36%; Syphacia muris (Yamaguti, 1935)2% and Trichuris muris (Schrank, 1788)10%; and 3 species of ectoparasites were diagnosed as follows: the Oriental rat flea Xenopsylla cheopis (Rothschild, 1903)2.0%, the spined rat louse Polyplax spinulosa (Burmeister, 1839)16.0%, and the mite Laelaps nuttalli (Hirst, 1916)4.0%. Endo-multiple infections had been noticed, as single (26%); double 50.0%; triple (22.0%) and tetra infections 2.0%. No significant differences were found between the sexes and weights of mice. The mice of Hayaskary and Langa were high infected with parasites. In the current study, we recorded the infection of the liver of Mus musculus with larval stage of Echinococcus granulosus (hydatid cyst) as the first natural infection in Iraq.