Ganoderma lucidum (Reishi), has been used in Traditional Chinese Medicine (TCM) for 5000 years or more. In China and Japan Ganoderma lucidum has been used in folk medicine, commonly in the treatment of neurasthenia, insomnia, hepatopathy, nephritis, gastric ulcers, asthma, and hypertension. In this study we have evaluated the effect of Ganoderma lucidum on hematological parameters in Wistar rats. The extract was given orally by gavage at the dose of 150 mg/kg and 300 mg/kg body weight. The result of our study shows extremely significant increase in the hemoglobin level, platelet count and leukocyte count more specifically at a dose of 150 mg/kg of Ganoderma lucidum extract when compare with normal control group. However, at a dose of 300 mg/kg of GLE, significant increase in hemoglobin level and extremely significant increase in leukocyte count were observed. Whereas, insignificant result was observed at both the doses of GLE in case of hematocrit level, MCV, MCHC, MCH and RBC count.