Stained blood smears of 51 domestic cats in Bangkhen district area in Bangkok were examined for blood parasites. Eight samples (15.89%) showed positive results of a Cytauxzoon-like ring form. Babesia spp. and Haemobartonella spp. were found 2 (3.92%) in number in each genus. Ten cats (19.61%) found an Ehrlichia-like in monocytes and neutrophils. Modified Knott s technique method was used to investigate microfilaria of Dirofilaria imitis and 3 samples (5.88%) were positive.