Abstract: Objective To compare effects of different dosage and exposure time of N-benzylhexadecanamide(NBH) with those of Maca extract on swimming time in male mice.Methods Sixty mice were divided randomly into 6 groups(control,7.5,0.5 NBH,1 800,180 and 45 mg/kg Maca extract,10 mice in each group),and NBH and Maca extract were orally administered continuously for 37 days.Thirty mice were divided randomly into 3 groups,namely,control,7.5 mg/kg NBH and 1 800 mg/kg Maca extract(10 mice in each group),and then NBH and Maca extract were administered only once.Whereafter experiments of loaded swimming were done and swimming time was recorded and statistically analyzed.In addition,the body weight of the mice were measured and analyzed before and after the experiments.Results Long and once oral administration of 7.5 mg/kg of NBH prolonged swimming time statistically(P<0.05) compared with the controls,and so did long oral administration of 1 800 mg/kg of Maca extract(P<0.05).The body weight of the mice was not statistically changed after the experiments.Conclusion N-benzylhexadecanamide and Maca extract have anti-fatigue effect in mice and N-benzylhexadecanamide is probably one of effective components of Maca.