In healthy individuals, intestinal parasitic infections generally self-limiting, but it may cause severe com-plications such as persistent diarrhea and/or mal-absorption in patients with immune compromising conditions (such as, undergoing chemotherapy, or-gan transplantation and AIDS). Hence, the main aim of this case-control study was to detect the intestinal parasites (Cryptosporidium spp., Giardia spp., En-tamoeba histolytica, Blastocystis spp. and Dientam-eba spp.) with microscopic and molecular methods among the immune compromised group consisting of Cancer Patients (CP) and Organ Transplant recip-ient Patients (OTP) in comparison with Healthy In-dividuals (HI) in Turkey