Abstract:The amino acid composition，molecular weight distribution，nutrient composition，trace elements，drug residues and acute oral toxicity test of Apostichopus japonicus oligopeptides were evaluated comprehensively.The anti-fatigue effects of Apostichopus japonicus oligopeptides，soybean oligopeptides and sea cucumber powder on mice were studied and compared.The mice were administered by oral gavage at three different doses （0.085，0.17，0.50 g/kg）.After being fed for 30 days，the loaded swimming time，the content of serum urea nitrogen and hepatic glycogen were measured.The results showed that Apostichopus japonicus oligopeptides had different kinds of amino acids and was rich in essential amino acids.Oligopeptide with molecular weight less than 1 000 Da was more than 98 %，mainly distributed at 180 Da-500 Da.It contained many kinds of trace elements.The content of taurine was high.It didn't contain veterinary drug，pesticide residues and heavy metals.The median lethal dose （LD50）was greater than 10 000 mg/kg by oral gavage.It was no toxicity and safety.Compared with the negative control group，Apostichopus japonicus oligopeptides，soybean oligopeptides and sea cucumber powder all had anti-fatigue effects.The order was Apostichopus japonicus oligopeptides ＞soybean oligopeptides ＞ sea cucumber powder.Each dose of Apostichopus japonicus oligopeptides significantly prolonged the loaded swimming time，decreased the content of serum urea nitrogen，and increased the content of hepatic glycogen significantly.However the dosage wasn't the higher the better，the best dosage was 0.17 g/kg.