A field experiment was conducted in order to evaluate the effects of soil amendments on soil air permeability under plastic mulching condition. The results showed that soil texture kept slight changes after applying soil amendments; however, it resulted in significant decrease of soil bulk density and increase of saturated water content and field capacity. Although plastic sheet mulch was helpful for soil water storage and heat preservation, it prevented air exchange at soil-atmosphere interface which led to decrease of soil air permeability. Meanwhile, soil structure and physical properties were improved through the application of soil amendments, resulting in clear air flow in soil pores, which led to increase of soil air permeability. Furthermore, the improvement of three types of soil amendment on soil air permeability were ranked in the order of phosphogypsum (PG) > polyacrylamide (PAM) > Handilong. As for PAM and Handilong treatments, high application rate had better effect on soil air permeability than that of low application rate. As for PG treatment, the value of soil air permeability under high application rate was 1.12 times as high as that under low application rate, and moderate and low application rates had similar effects on soil air permeability. The results indicated that soil amendments could obviously improve soil air permeability, which certainly provided new methods for improving soil air permeability during field crops growth.