Nutmeg, the dried seed kernel of Myristica fragrans, MF (Family: Myristicaceae) possesses antifungal, hepatoprotective and antioxidant properties. Its radioprotective effect against 6, 8 and 10 Gy gamma radiation was evaluated by 30 day survival assay. Regression analysis yielded LD(50/30 )as 6.83 Gy and 8.89 Gy for irradiated only and (MF + radiation) groups, respectively. The dose reduction factor was computed as 1.3. Administration of MF significantly enhanced hepatic glutathione (GSH) and decreased testicular lipid peroxidation (LPO) level whereas acid phosphatase (ACP) and alkaline phosphatase (ALP) activity did not show any significant alteration. Irradiation resulted in significant elevation in LPO level and ACP activity, and decreased the GSH content and ALP activity. MF pretreatment effectively protected against radiation induced biochemical alteration as reflected by a decrease in LPO level and ACP activity, and an increase in GSH and ALP activity. The present study has implications for the potential use of MF as a radioprotector.