Yield data collection is the one of the most important parts of field information acquisition, and also an important component in precision agriculture technical practice. There is currently no domestic-produced yield monitor in China and the similar foreign product made is very expensive. Therefore, the development of a yield information gathering system of combine harvester intellectual property becomes an necessity.The selection and performance of yield acquisition system hardware was firstly introduced in this paper, and with the whole research focusing on the hardware and software design of the system. And the modularized designing method was adopted in the overall plan of this system. The designing of system hardware employed 80C592 MCU of PHILIPS as the core; and the analog signal from the sensor was converted through the A/D channel to achieve real-time yield acquisition. And serial port was used to expand the GPS receiver module for accurate acquision of the geogrgphical position. The CF card interface is expended using the p0 and p2 port, and the system could store information from the sensor and the GPS in the CF card, which realized the writing and reading of CF card and made the massive data storage a possibility and the data processing more convenient. And LCD interface was expended using P1 port; it displays the information acquisitioned from the sensors and GPS and conducts human-machine interaction.In order to facilitate debugging, transplantation and modification of the system, in software design the idea of modularized design and subprogram were adopted; System software includes the main program, data collection and A/D conversion subprogram, GPS receiver subprogram, CF card memory subprogram, Timer interrupt subprogram and so on.The software proteus and keil?c was used for integrateed simulation of the system; proteus was used for hardware simulation and keil c for software simulation. The emulational results and design requirements are basically in correspondance. By running the simulation, this system has these advantages of simple circuit; hign degree of automation and reliable data acquision ability.The system has great practical significance for improving the intelligent and automation level of combine harvester.