Provided is a dental pretreatment material for dental tissue regeneration with use of dental pulp stem cells, in particular, a dental pretreatment material enabling effective dental tissue regeneration even with use of dental pulp stem cells derived from an individual of middle or advanced age. The dental pretreatment material includes a serine protease, specifically trypsin. The dental pretreatment material including trypsin is injected in a root canal before a root canal filler including dental pulp stem cells and an extracellular matrix is inserted to regenerate dental pulp and dentin. The root canal filler includes an ALK5 inhibitor, a CCR3 antagonist, or a CCL11-neutralizing antibody.