Cryptosporidium parvum and Giardia lamblia are the most common zoonotic intestinal protozoan parasites causing diarrheal diseases Cryptosporidiosis and Giardiasis are significant health concerns in both humans and animals; for this reason, these parasites acquired public and veterinary importance. Dogs and cats are susceptible to infection and play an important role in transmitting these protozoans to human. Recently in Iraq, there is an interest in keeping pet animals and an increase of stray cats and dogs which accompany livestock. Some people started to attract stray cats through feeding and became like house animals. This literature review focused on the results of Iraqi researchers to overview the importance prevalence of these parasites on both human and animals. This literature review recommended to educate pet owners especially children and follow veterinarians' instructions, to control and prevent transmission of these zoonotic diseases and future researches should focus and investigate from these finding and highlight the role of domestic animals in transmission of these diseases.