series of films were prepared by polyelectrolyte complex(PEC) formation between $alpha$-keratose and chitosan having different molecular weights and degrees of deacetylation. The biodegradability of these PEC films was examined by incubation at 37$^{circ}C$ in the phosphate buffersoulution(pH 7) containing lysozyme. The high biological absorbability of the $alpha$-keratose was retarded by the complex formation with the chitosan. The degradability of the PEC films was affected by the degree of deacetylation and the molecular weight of the chitosan, i.e., the degradation rate of the PEC films increased as the degree of deacetylation or the molecular weight of the chitosan decreased. Therefore, it was suggested that the biodegradability of $alpha$-keratose and chitosan can be controlled by changing the above factors adequately.