In this research the effect of Camellia sinensis on Ctenopharyngodon idella hematological factors was studied. For this purpose 240 juvenile of Ctenopharyngodon  idella was selected that initially had average weight of 18.24+2.07 gr and after being adapted with environment, were stored  in 12  tanks selectively (20 fish  in each tank). The camellia siensis was added to the diet in three levels 1.5% (treatment 2) 3 % (treatment 3) and 5 % (treatment 4) and the diet without camellia siensis was used for control group (treatment 1). Each treatment was repeated 3 times. The fish was fed 3% of their weight. At the end of the 60 day period, 15 fish was randomly selected from each treatment and their blood sample was taken from the caudal vein. The result was showed that amount of RBC and WBC had significant difference in treatment 2 with other treatments (P<0.05). The Maximum amount in treatment 2 (1.5%) was 4.4±0.57 (microliter×10³) and 6.74±0.74 (gr/dL), respectively. The most improved Biochemical factors were seen in treatment 0.5 %. Increasing the number of white blood cells and hemoglobin in the treatment of 1.5% and in the average concentration of globules showed an increasing trend in the treatments of green tea and also a significant increase in serum biochemical factors including albumin and glucose at the level of 1.5%. Results showed that adding camellia siensis to Ctenopharyngodon idella diet in 5 % level comparing to other levels can relatively improve investigated biochemical factors.