The paper presents a method of chitin chemical modification leading to the butyric-acetic chitin copolyester (BAC) with properties that predispose it to applications as a wound-healing dressing. The paper shows the possibility of using chitins of various origins for the production of ester derivatives. The possibility of using chitin obtained from honeybees, krill and crab has been shown. The BAC was obtained by esterification of chitin with a mixture of butyric and acetic anhydrides. A method for producing fibers and flat porous materials for medical applications from this polymer is presented. The results of biological tests of the produced BAC structures are also shown.