PROBLEM TO BE SOLVED: To provide an adhesive composition for dentistry which exhibits sufficient adhesion effect by simple operation without requiring acid catalysts, while having flexibility to be capable of being used for all of noble metals, non-noble metals, and alloys thereof, ceramics, and resins, for dentistry.SOLUTION: An adhesive composition for dentistry consists of a silane coupling agent containing a polymerizable group, a thiopropionic acid derivative or a thioglycolic acid derivative, and a volatile organic solvent. The adhesive composition for dentistry is mixed with a volatile organic solvent, and it is used as a tooth surface-treating agent. The adhesive composition for dentistry is mixed with a dental resin, and it is used as a dental resin.