The present invention is a device for producing a silicon single crystal by a CZ process, said device being provided with a chamber having, arranged therein, a heater for heating a raw material and a means for cooling the chamber by a cooling medium. The device for producing a silicon single crystal is equipped with: a means for measuring an inlet temperature, an outlet temperature and a flow amount of the cooling medium, which can cool the chamber, in a flow path through which the cooling medium flows in the chamber; a calculation means for calculating the amount of heat to be removed from the chamber on the basis of measurement values for the inlet temperature, the outlet temperature and the flow amount; and a heater electric power control means for controlling the electric power of the heater on the basis of a calculated value of the amount of heat to be removed. According to this constitution, the electric power of the heater can be controlled on the basis of the amount of heat to be removed from the chamber which is calculated from the measurement values for the temperatures and flow amount of the cooling medium, and therefore it becomes possible to provide a silicon single crystal production device which enables the pulling up of a single crystal at a crystal diameter and a crystal pull-up rate both of which are closer to intended values.