Abstract: In order to apply a cruise control system (CCS) to the tractor with less labor intensity, such as sowing and spraying, a electro-hydraulic automated mechanical transmission (AMT) was developed, a automatic adjusting mechanism of throttle was designed, a single chip microcontroller using advanced RISC machine 7(ARM7) was exploited and incremental proportional-integral-differential control algorithm was designed based on the platform of tractor of FOTON LOVOL TG1254 in this paper. The designed CCS was tested at different speed on the concrete road, the experimental results indicated that the developed CCS run reliably and stably, the speed control accuracy was less than 0.2m/s,it meets the need of cruise control. It provides a hardware foundation for realization cruise control of tractor at different speed.