In order to investigate the adaptability of the developed taped type rice direct seeding machine for field surface roughness, dynamic simulated experiments were carried out. A field surface roughness measuring system composed of two angular displacement sensors, an A/D converter, a computer etc. was designed according to the structure and working principle of the seeding machine. The two types of field surface roughness, one known as original field surface roughness formed by the working of rotavator and the other known as rolled field surface roughness formed by the roller of the seeding -machine,were detected. The signals were analyzed in timedomain and frequency-domain by using Matlab software. Transfer functions were established by the method of identification, and the dynamic characteristics of the system were analyzed. The results showed that the “soil-machine” system is linear with the first order typical feature. The dynamic characteristics of the systems such as rapidity, bandwidth and soil covering thickness are able to satisfy the requirements of rice seeding technology. 