Smoking is the second leading cause of death in the world. It has many adverse effects on organs and systems of body. Rapidly increased rate of smoking in all over the world is the largest threat for the health. Smoking may change different cellular components of blood. Different chemicals especially nicotine changes the chemistry of blood. This study was designed to investigate the adverse effect of smoking in hematological parameters in male and female smokers. A total of 200 subjects participated in the study including 100 males (50 smokers and 50 non-smokers) and 100 females (50 smokers and 50 non-smokers). Complete blood count (CBC) was performed to analyze the hematological changes between the smokers and non-smokers control group by using HumaCount 60 TS. Statistical analysis was performed in SPSS version 20. CBC test was performed to calculate the values of different parameters in blood. Significantly higher values of hemoglobin (Hb), Red Blood Cells (RBCs), White Blood Cells (WBCs) and MCHC (mean corpuscular hemoglobin concentration) were observed in male smokers (P<0.05) than non-smokers. Female smoker showed significant increase in Hb level and PCV (Hematocrit) as compared to nonsmokers and the difference was statistically significant (P<0.05). Comparison of hematological changes in male smokers and female smokers showed significant increase in WBCs count of male smokers. Our findings showed that both male and female smokers have high leucocyte count that serves as a risk factor for certain diseases like cardiovascular diseases and chronic obstructive pulmonary disease.