Sixty six (64) Sprague- dawley rats (average weight 150 - 240 g) of each sex were used for the experiment. The animals were acclimatized, maintained and housed in laboratory for 28 days. At the end of the study animals were anesthetized and were sacrificed by cervical decapitation. Blood was collected via cardiac puncture and studied for White blood cells (WBC), Red blood cells (RBC), Haemoglobin (HGB), Hematocrite (HCT), and Platelets (PLT) by Using Operon hematology analyzer. In the present study, hematological findings among the treated and control groups of rats, we found that the hematological parameters were disturbs on the treatment of anti -TB drugs ETH and PAS. Whereas we observed that after administration of seed extract of Piper nigrum independently or in combination with the anti -TB drugs, the hematological parameters were improved towards normalization.