In order to investigate the optimal amount of wheat straw coverage in facility rice fields. Plastic cultivation boxes were utilized for water spinach planting inside a greenhouse, with wheat straw volumes of 22.50 t/ha and 37.50t/ha implemented as soil surface coverings in comparison to a control group without straw coverage. Three replicates were performed for each set. This study was conducted to study the effects of different soil straw mulching on the yield and soil fertility of summer and autumn water spinach. The results showed that the decomposing rates of wheat straw were 67.48% and 62.91% in 22.50 t/ha and 37.50 t/ha straw covering treatments, respectively. The total yield of the two treatments was higher than the control. The yield of the two treatments and control were 8 624,8 142, 8 025 kg, respectively. The content of flavonoids in treatment was higher than that in control, and the quality of plant was improved; the content of total phosphorus in both treated plants was higher than that in the treated plants. Post-harvest soil organic carbon content of the two treatments increased by 4.29% and 1.18%, respectively,and the control decreased by 5.01%, which effectively alleviated the decrease of organic carbon content caused by plant growth and absorption; the nitrate content of the treated soil decreased after planting. The content of available P and K increased, and the coverage of 37.50 t/ha increased by 48.01% compared with the control. The activity of invertase in the two treatments decreased after planting, but the decrease was significantly lower than that of the control22.50 t/ha. The urease and acid phosphatase activities increased, suggesting that wheat straw mulching can boost soil enzymatic activity.