To provide a jig for dental implant investment which does not damage nor deform a polygonal projecting section positioned on the inner side of a screw type implant fixture in the oval cavity of a patient at the time of burying the fixture in a burying-in hole formed into the jawbone of the missing tooth portion of the patient in the course of dental implant treatment.

On this jig 2 for dental implant investment which is used for burying the screw type implant fixture 1 having a screw 1a on the outer peripheral surface of its part buried in the burying-in hole formed into the jawbone of the mixing tooth portion of the patient in the burying-in hole, a recessed removed section B is formed in the whole portion corresponding to the corner section of a polygonal recessed section engaged with the polygonal projecting section 1c provided on the inside of the implant fixture 1 in the oval cavity of the patient.