In order to investigate the effect of cotton straw returning after，different amount of field trials，and cotton field soil physics，chemistry indicators were analyzed according to the different cotton growth periods.The results showed that both kinds of processing 0~10 cm soil layer increaseand reducet the same time the were respectively presented positively and negative correlation with the amount of returned straw.When the amount of farmland 9 t/hm2，the proportion of clay and silt increased.pH of topsoil (0~10 cm) in cotton boll opening period.treatment were significantly reduc，and with increasing the quantity of returning.Returning process effectively reduce the in the soil.The effects of reducing SO-24 content and increasing the content of K+，Ca2+ and Mg2+ in 0~10 cm soil layer were the most obvious when the amount of 9 t/hm2.treaments significantly increase soil organic matter content.increasing soil total nitrogen and available potassium content，，but the effect on available phosphorus opposite.The two treaments effectively increase cotton production，and the FS better than th FC.Cotton straw returning not only improve soil physical and chemical properties but also reduce the waste of resources.