An object is to provide a polymerization apparatus for dental technique with which both of preliminary polymerization and final polymerization can be carried out by one apparatus. The apparatus includes a plurality of light sources whose light axes run at least in two directions a cover that covers the light sources, forms a polymerization space inside thereof and switches a formation and closure of an opening that communicates inside and outside the polymerization space a sensor that detects the formation and closure of the opening by the cover a controller that receives signals from the sensor, and based on the formation and closure of the opening, turns on some of the light sources having two or more directions of light axis with the opening closed, and turns on some of the light sources having fewer directions of light axis than with the opening closed, with the opening open.
