The present study was conducted to determine the prevalence of trichomoniasis and its effect on some blood parameters in pigeons. A total of 100 samples from the pigeons (50 wild and 50 domestic) were collected during the months of March and April 2005. Higher prevalence (P<0.05) was recorded in wild pigeons (60%) than in domestic pigeon (26%). The overall prevalence recorded was 43%, being non significantly higher in April (56%) than in March (30%). In infected pigeons, there was significant (P<0.05) decrease in hemoglobin concentration number of monocytes packed cell volume, body weight, than healthy birds. Likewise, the values of total leukocyte count, lymphocyte and eosinophils were higher significantly (P<0.05) in infected pigeons than the healthy ones. While, no significant difference was observed for hetrophils count when infected and healthy birds were compared. It was concluded that trichomonad infection is quite common in wild, as well as in domestic, pigeons under the prevailing cage system.