In this study 737 stool specimens were collected from people attending some primary health care centres and hospitals in North of Baghdad, during the period from beginning of April 2009 till the end of March 2010. Different factors were examined to be related with the prevalence of Cryptosporidiosis which were (number of family member, travelling history, source of drinking water and domestic animal present). Significant relations (p≤0.05) were observed between infection rate and the following factor: -Number of family member: The high percentage of Cryptosporidium spp positive cases were seen in families composed of (15-19) and (more than 20) individual which were 28.32% and 16.37% respectively when compared with other family clusters -Travelling history: infection rate was higher in patients with travelling history 38.8%, than patient without travelling history 14.81%. -Source of drinking water: persons who consumed boiled water showed the minimum rate of infection which was 5% when it compared with other persons who consumed tap, filtered and bottled water. While there was no significant relation between the presence of domestic animals and rate of infection, although it was higher in patients who had domestic animals in their household 19.49% than those who had no domestic animals in their household 13.89%