The invention relates to the field of automatic control in industrial production, particularly an automatic control system for Kyropoulos-process sapphire crystal growth. The invention is characterized in that the automatic control system mainly comprises a microprocessor, a touch screen, an audible and visual alarm circuit, a control cabinet, an upper computer, a vacuum meter, a heating power source, a rotary variable-frequency motor, an elevating variable-frequency motor, a weighing sensor and an elevating stepping motor, wherein the microprocessor is the core unit of the whole automatic control system, implements communication and control with the control cabinet, upper computer, vacuum meter, heating power source, rotary variable-frequency motor and elevating variable-frequency motor through an RS-485 bus, implements communication with the touch screen and weighing sensor through an RS-232 bus, and controls the operation of the elevating stepping motor and audible and visual alarm circuit through an I / O port. The multi-physical-quantity detection and control system in the Kyropoulos-process sapphire crystal growth process is designed on the basis of the embedded microprocessor, implements automatic control on the whole crystal growth process, lowers the dependence on the artificial intervention and technology capability of operating personnel in the crystal growth process, reduces the labor amount of the operating personnel, and enhances the standardability and crystal quality of the crystal growth operation process.