Disclosed is a kit for adhesion between an alginate impression material for dental use and an impression tray, which contains: (U) a pretreatment agent that contains (I) 100 parts by mass of an organic solvent that has a solubility parameter (´) of 17.0-23.0 [(MPa) 1/2 ] and (II) 0.1-30 parts by mass of inorganic particles having an average particle diameter of 10 µm or less； and (V1) an adhesive that contains (I) a polyamine compound that contains two or more amino groups in each molecule and (III) a lower alcohol solvent. Also disclosed is a kit for adhesion between an alginate impression material for dental use and an impression tray, which contains: (U) a pretreatment agent that contains (I) 100 parts by mass of an organic solvent that has a solubility parameter (´) of 17.0-23.0 [(MPa) 1/2 ] and (II) 0.1-30 parts by mass of inorganic particles having an average particle diameter of 10µm or less； and (V2) an adhesive that is obtained by mixing (I) a polyamine compound that contains two or more amino groups in each molecule, (II) an organic peroxide and (III) a lower alcohol solvent.
