The simulating test is the important means and method to reduce cost and raise efficiency of new type of farm machinery design. According to the actual working circumstances of farm machinery in the paddy field, a trial soil bin which could imitate actual work in field was designed. The project and process of the soil bin design were introduced briefly. The methods to resolve the problems such as how to make the wet soil and how to control the water content of soil were proposed; based on the analysis of the functions and characteristics of the soil bin, experimental data sampling system was developed. 