To provide a shrinkage fitting holder superior in rigidity and gripping force, and capable of setting a tool mounting position (setting of a projecting amount of a tool blade) with high accuracy.

A projecting cylindrical small part 4a is formed on a point of a chuck part 4 of a shrinkage fitting holder 1 having an insertion amount control tool 6 for adjusting an insertion amount of a tool when necessary, and a ring of high coefficient of thermal expansion is mounted on an outer periphery of the point of the chuck part 4 or the small part 4a by shrinkage fitting, whereby a mounting position of the tool can be set with high accuracy, and the tool can be fixed with high rigidity and gripping force.