Because of the low automation level of traditional diamond drill sintering machine in China, it is difficult to flexibly deal with the requirements of diamond bits of different formula in hot pressing process, temperature and pressure. A new hot-pressing intelligent sintering machine for diamond bit is developed. It integrates optical, electricity and hydraulic pressure, taking the microcontroller as the core device of the control system and using fuzzy PID control theory to monitor and control the sintering temperature and pressure in real time to achieve prestoring process automatic operation, the control effect meets the needing of bit sintering process. The paper analyzes the influence of the working principle, temperature and pressure parameters of this hot-pressing sintering machine on the quality of finished bits and introduces its control system design matched with hot press.