By the field experiment, we set up the treatments of non-application of potash fertilizer, conventional fertilization, balanced fertilization and halved application of potash fertilizer, and studied the effect of different treatments on rice yield and soil nutrient content. The results showed that compared with non-application of potash fertilizer, conventional fertilization and balanced fertilization significantly increased the spike length, thousand kernel weight, yield and total potassium content of the stalk, as well as soil organic matter, total nitrogen and available phosphorus content; compared with conventional fertilization, the balanced fertilization did not significantly increase the rice growth and yield, but effectively increased rice grain total nitrogen, stalk total nitrogen and total phosphorus content, as well as soil available phosphorus and available potassium content. It could be found that potash fertilizer played a certain role in increasing rice yield and soil nutrient content, and the balanced fertilization had the most significant effect.