This investigation was carried at the Experimental Laboratory Unit, Division of Animal Production Technology, Faculty of Technology, Mahasarakham University, Mahasarakham, Thailand in August to December 2004. Three different breeds of poultry were used, i.e., Thai indigenous, Thai indigenous crossbred and broiler chickens. The experiment was laid in a split plot design with three replications. The three poultry breeds were used as main plots, whilst gender (male and female) and sampling periods were used as subplots. An assay on blood characteristics and blood counts of red and white blood cells were carried out. Feed intake and average daily gained weight (ADG)/week were determined. The results showed that the appearances on blood cells characteristics of erythrocyte of red blood cells and white blood cells of heterophil, eosinophil, monocyte, basophil and thrombocyte of the three poultry breeds were not different from one another. Hematological values of the three different breeds possessed normal blood values for normal growth and they fitted within a normal range of blood of normal chickens. Hemoglobin concentration (Hb) of Thai indigenous chickens was higher than both Thai indigenous crossbred and broiler chickens. White blood cells ofheterophil of Thai indigenous crossbred chickens were higher than broiler chickens, whilst white blood of lymphocyte of female was higher than female. However, the differences found on hematological values of both male and female were not statistically significant. Daily feed intake/week and average daily gained weight increased/week of broiler chickens ranked the highest followed by Thai indigenous crossbred and the lowest was with Thai indigenous chickens.