INTRODUCTION: Involvement of the furcations of multirooted teeth represents a challenge in the treatment of periodontal disease, both from a prognostic perspective and from the perspective of therapeutic measures. OBJECTIVES: the current investigation was conducted to evaluate the regenerative potential of chitosan membrane in the management of critical size grade II furcation defects and to compare it with conventional therapy using collagen membrane. MATERIALS AND METHODS: A total number of four adult systemically healthy mongrel dogs were included in the current study. Grade II critical-sized furcation defects were surgically created with respect to lower premolar teeth. In all four dogs, the right quadrants received chitosan membrane with natural hydroxyapatite. Whereas, the left quadrants received collagen membrane with natural hydroxyapatite. RESULTS: The present study observed that chitosan was better than collagen regarding mean bone surface area (P < 0.05) and the difference was statistically significant. CONCLUSIONS: Chitosan membrane is an effective, easy to handle, cheap membrane that can be used in periodontal regeneration of furcation defects. Chitosan membrane showed superior periodontal tissue regeneration when compared to collagen membrane in the mangement of such defects