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Rice is one of the main grain crops in China. Improving the mechanization level of rice production can enhance the comprehensive agricultural production capacity of China. Solid ridge is important guarantee for irrigation and rice growth. It can improve the yield of grain crops and reduce the waste of water resources. In order to improve the efficiency and quality of ridging operation in paddy field, reducing the labor intensity and solving the problem that the ridge can not be built mechanically at the corner of the paddy field, a bi-directional ridger for paddy field was designed, whose rotary tillage and repression components can rotate horizontally. The structural design and working principle were conducted for key components, such as offset system and 180° horizontal rotary adjustment mechanism. Kinematic analysis of the offset system was carried out and the structural parameters of the moving parts were obtained, which satisfied the migration requirements under different working conditions. The motion model of the 180° horizontal rotary adjustment mechanism was established, the conditions for stabilizing the rotary tillage component and compacting assembly were determined. The performance test of the prototype in paddy field was completed. Test results showed that during the advance operation and reverse operation, the average value of the ridge firmness was increased with the increase of interval time and the coefficient of variation of the ridge firmness was decreased with the increase of the interval time when the speed was 1.5km/h, 2.0km/h and 2.3km/h. The average value of the ridge side was higher than that of the top of ridge at the same interval time. The stability values of the measured positions of the ridge were not less than 1332kPa. The two methods of operation met the agronomic requirements of paddy fields and the performance of the ridger was stable in the process of advancing and reversing, its ridge had good quality, which was solid and smooth and could meet the requirement of paddy field production.