Cryptosporidium parvum and Entamoeba histolytica are significant protozoan parasites that adversely impact human health. The infection rate of these parasites among diabetic patients was recorded at 18.33%. However, the mechanisms underlying host-parasite interactions remain poorly understood. It was noted that the percentage of E.histolytica was 40%, while that of cryptosporidiosis was 15%, but the interaction between the parasite and the host is not well understood. The results also showed an increase in the C3a/c3aR ratio in diabetic patients infected with intestinal parasites compared to healthy individuals. C3a works by binding to C3aR on the cell surface and has a repair function in intestinal parasite and is important in regulating the immune response. C3a expression levels were analyzed using polymerase chain reaction and compared with the results of Housekeeping gene, which were higher than C3a expression levels, because C3a gene expression is host-specific, it can be influenced by many pathogens in the patient.