Background: Transplantation of the developing teeth has been done many years ago with different aims either for studying odontogenesis or replacing missing or un- erupted teeth with a biologic replacement. This process has been done either in the jaw of the same individual or animal (auto- transplantation) or in the jaw of another experimental animal. Objectives: This study was designed to investigate the effect of autotransplantation of the developing third permanent premolar tooth germ to the fresh extraction socket of the permanent canine in dogs. Methods: Twenty dogs of non-defined breed from both genders, weighting 2, 5 -3 kg and their ages between 45-60 days were used in this study. The developing right permanent mandibular third premolar were autotransplanted to the fresh extraction socket of the developing permanent canine after removing the deciduous and permanent canine under general anesthesia. After 30 and 60 days of transplantation, CT scanning (Computerized Tomography) and histological analysis using H&E (Hematoxylin and Eosin) and Masson's trichrome stains were done. Results: The transplanted premolar formed enamel and dentin as the control premolar in the opposing side but there was appearance of different structures as osteodentin and pulp stone. After 60 days CT scanning for the site of the transplanted third permanent premolar showed disappearance of the hard structure suggesting resorption of the transplanted premolar, which were confirmed by the histological analysis. Conclusions:Our initial results after 30 days were promising and showed that transplantation of tooth germs at early stage of development was possible and the transplanted germ continued in development as the inner enamel epithelium differentiated into ameloblasts and secreted enamel matrix and odontoblasts differentiated and secreted dentin matrix. And the later failure of the transplanted germs to continue after 60 days suggested that we need further research work in transplantation of permanent tooth germs in dogs.