The purpose of this study was to determine the gingival response to the various restorations for 3 weeks, 5 weeks and 8 weeks respectively after they had been inserted in 36 tooth of 3 dogs. The histopathological observation was also performed to evaluate the effect of the various restorations on gingival tissue. They included gold, copper and nickel-chrome alloy. The following findings were obtained. 1. The gingivae adjacent to the well adapted and polished restorations and their margins with a level of gingival crest were grossly and histopathologically found no specific changes. 2. The gingive adjacent to the ill fitting and unpolished restorations and their margins with subgingival extension of 1 to 1.5mm were not grossly found any changes. 3. There were no obvious difference in gingival response among the various alloys in histopathological observation.