Random copolymers based on 6-aminocaproic acid and alpha-L-alanine were prepared by melt phase polycondensation method and characterized by FTIR, H-1 NMR, DSC and WAXD. The density, water absorptivity and enzymatic degradation of copolymers were measured. The results show that with increasing of alanine content in comonomers, the density, water absorptivity and rate of enzymatic degradation of copolymers increase, but the intrinsic viscosity and the degree of crystallization decrease. When the molar percentage of alanine increases to 40% in comonomers, copolymer is amorphous.