Weeds growing in paddy fields are one of the main reasons for the decline of rice yield and quality. Effective weed removal can provide good growth conditions for rice. In order to improve the efficiency of mechanical weeding, reduce the labor intensity, and solve the problems of low weeding rate and high seedling injury rate in the operation of rice field, a weeder between rows in rice field based on remote control steering was designed. The overall structure and working principle were described, and the mechanical model of weeder was established. Through static analysis, the maximum driving torque of active weeding wheel was 49.42N·m. The steering mechanism was designed according to Ackerman’s steering principle, and the theoretical value of the maximum driving torque required by trapezoidal steering mechanism was 4.57N·m. The steering control system was designed to realize the function of automatic steering and receiving feedback information through remote control. The steering performance test was carried out, and the actual change of steering angle was recorded and compared with the theoretical change. The test results showed that the maximum deviation between the theoretical angle and the actual angle was 1.3°, and the control system had high precision, which met the steering requirements of the actual operation in the field. The weeding performance test was carried out, and the field test results showed that the average weeding rate of the weeder was not less than 77.9%, the average injured seedling rate was not more than 3%, which can meet the requirements of weeding agronomic index in paddy field.