Abstract: In order to explore the method of improving coating quality between paper mulch and paddy mud, the effects of paddy mud water content, vertical pressure and load speed on the paddy mud adhesive force were studied through experiments, and then the corresponding mathematical models were established. Results showed that when water content was 34.5%~35.5%, with the increase of water content, viscosity and adhesive force of paddy mud declined sharply; When water content was more than 35.5%, the effect of water content on viscosity and adhesive force was not significant. With the raise of paddy mud viscosity, the adhesive force increased logarithmically; With the increase of vertical pressure, the adhesive force between paddy mud and paper mulch increased linearly. When load speed was 0.83×10-3～0.5×10-2 m/s, the adhesive force increased rapidly with load speed increased; But when the load speed was more than 0.5×10-2 m/s, the adhesive force increased slowly; When the load speed was 0.67×10-2～0.83×10-2 m/s, the adhesive force was to constant value. Consequently, during land preparation and steeping field, to improve the coating quality of paper mulch, the maximal water content of the soil should be not more than 1.05 times of saturated water content; On the premise of meeting mud compressive strength, it should increase unit area pressure of paper mulch; When the speed of paper coating was less than 0.5×10-2 m/s, the coating quality could be improved through uploading speed method .The research results can provide a reference for design of paper mulching mechanism.