Oral administration of laboratory cultured mycelia powder of C. sinensis did not show any sign of toxicity as no significant change was observed in organ weight and serological parameters in rats. However, there was a significant increase in food intake, body weight gain and hematological parameters like WBC, RBC, Hb and lymphocytes in treated groups. Histopathology of vital organs also supported the non toxic effect of C. sinensis. The results conclude that laboratory cultured mycelia powder of C. sinensis is safe and non toxic up to 2 g/kg body weight dose.