N-acryloyl- glucosamine (AGA) and poly(ethylene glycol) diacrylate (PEGDA) were used to prepare hydrogels via an in- situ forming procedure with photopolymerization,and1 H NMR was employed to reveal the com-position variation of AGA/PEGDA system during the gelation.Then,the chemical composition and morphology of lyophilized hydrogels were evaluated by means of FT- IR,XPS and SEM,and the effects of photoinitiator mass con-centration,AGA dosage and PEGDA dosage on the swelling ratio and the crosslinking yield were investigated.The results indicate that glucosamine is successfully incorporated into PEGDA hydrogel network,that the crosslinking yield reaches the maximum at a photoinitiator content of 0.6g/L,that the crosslinking yield of hydrogels decreases with the increase of AGA dosage but decreases first and then increases with the increase of PEGDA dosage,that the swelling ratio of hydrogels decreases with the increase of AGA and PEGDA dosages,and that a shrinking surface may occur at high AGA dosage.