The preparation of α-glucosidase inhibitory peptides was gotten, which was derived from ginkgo biloba by enzymatic hydrolysis with papain. A factorial design experiment was conducted, while, the effects of concentration of substrate, pH, E/S ratio, extraction temperature and time were studied. And then, it was fractioned by using membrane ultrafiltration with molecular weight cutoffs of 100, 50, 30, 10 and 3 kDa. The results showed: with the concentration of substrate 1.5%, pH 7.36, E/S ratio of 5 g/100 g, temperature of 57.9 ℃ and extraction time of 4.4 h, the inhibitory activities ofα-glucosidase was the highest, and reached 17.18%. The inhibitory activities of α-glucosidase, peptide fraction <3 kDa, exhibited the highest and reached 50.43%. Therefore, the ginkgo protein hydrolysate or its active peptides can be used in foods against hypertension and related diseases.