Faecal specimens of 305 pet dogs that were reffered to the Small Animal Clinic of Tehran University were collected for parasitology examination. Direct and formal-ether methods as well as trichrome and modified ziehl-neelsen staining techniques were applied for parasite identification. The results indicate that, 65(21.3%) of specimens were infected with protozoa or helminthes. The parasites were identified as follows: Giardia intestianlis 1.63%, Cryptosporidium parvum 1.63%, Isospora spp 7.21%, Blastocystis sp. 0.32%, Toxascaris leonina 3.27% Toxocara canis 6.55%, Hook worms 2.62% and Taenia spp 2.29%. Two questionnaires, about demogrphic data of dogs as well as knowledge of dog owners about zoonotic risk of parasites of dog were administered to the owners. Majority of the owners were not found to be aware of the potential risk of canine parasites to human health and their knowledge were found unsatisfactory.