Abstract: Low molecular weight(Da<1000)Polyethylene glycol(PEG)/water system was applied in extracting jackfruit peel polysaccharides(JFP),by single factor experiment to investigate the effect of polyethylene glycol/water system and ultrasonic-microwave assisted extraction(UMAE)conditions on the extraction of polysaccharide from Artocarpus heterophyllus Lam. peels,and it was compared with pure water. The extraction process was optimized by response surface experiment,the antioxidant activity of polysaccharides under the best extraction process was studied,and the differences of infrared spectrum and ultraviolet spectrum respectively were also analysised. The result indicated that the optimum conditions for UMAE extraction were as follows:Concentreation of PEG-200 0.34 g·mL^-1,microwave power 68 W,extraction time 32 min,solid-liquid ratio 1:42 (g/mL).Under these conditions,the extraction of polysaccharides(JFP-P)was15.65%±0.29%,which was 30.31% higher than that with water as a solvent(JFP-W). Overall,regarding antioxidant activity,two polysaccharides showed no significant difference in reducing power and the scavenging capacity to DPPH radicals and OH radicals(p>0.05). The infrared and ultraviolet spectrum indicated that both polysaccharides had classical absorption peak characterized in polysaccharides and didn't contain nuclein and protein. The results showed that thelow molecular weight(Da<1000)polyethylene glycol/water system combined with ultrasonic-microwave assisted technique could be effectively applied to extract polysaccharides from jackfruit peel.