The present study was performed to evaluate histomorphological difference in various surface-treated implants in beagle. Implants($Implantium^{(R)}$, Dentium Co. Korea) with pure titanium machined surface, acid treated surface, and $Al_2O_3(50{sim}100;{mu}m)$blasted with acid treated surface were used in this study. All mandibular premolars of $1.5{sim}2$ year old male beagle dogs were extracted. At 3 months after extraction, the implants(${Phi}$ 4mm, l 6mm) were installed. The beagle were sacrificed at 1, 3 months after installation and then tissues including implants were prepared for non-decalcified specimens. These specimens were analyzed comparatively under light microscope. The results of this study were as follow 1. Higher rate of osseointegration were showed in the $Al_2O_3(50{sim}100;{mu}m)$blasted with acid-treated surface. 2. Increased osseointegration were showed in the $Al_2O_3(50{sim}100;{mu}m)$blasted with acidtreated surface with time. 3. Higher maturation of integration were showed in the $Al_2O_3(50{sim}100;{mu}m)$blasted with acid-treated surface. In conclusion, surface treatment of $Al_2O_3blasted$ with acid might be considered to shorten healing time and improve success rate as increasing contact of implant and bone.