Objective To explore the hypoglycemic effect of gelidium amansii polysaccharide.Method The rat alloxan-induced diabetic model was established and 50 rats with their blood glucose >16.1 mmol/L were chosen and ramdonly divided into five groups: namely group with high-dose gelidium amansii polysaccharide（2400 mg/kg）

group with medium gelidium amansii polysaccharide（1 200 mg/kg）

group with low-dose gelidium amansii polysaccharide（600 mg/kg）

group treated with glipizide（1.8 mg/kg） and the model control group.The effect of different dosages of gelidium amansii polysaccharide on blood glucose

serum insulin and glucagon were observed.Results The group with high-dose and medium gelidium amansii polysaccharide may reduce the blood glucose of alloxan-induced diabetic rats and compared with the model control group

each difference was statistically significant（P<0.05 or P<0.01）.The group with high-dose agar polysaccharide could improve the insulin level

reduce the concentration of glucagon

and the difference

compared with the model control group

was statistically significant（P<0.01）.Conclusion The gelidium amansii polysaccharide has hypoglycemic effect in diabetic rats.