Abstract: To determine the control efficacy of pre-emergent treatment of pyroxasulfone mixed with flumioxazin on weeds in soybean and maize intercropping field, field efficacy experiment was carried out. Five treatments were set: T₁（40% pyroxasulfone suspension agent and 51% flumioxazin wettable powder 180 + 30.60 g a.i./hm²）, T₂（40% pyroxasulfone suspension agent and 51% flumioxazin wettable powder 165 + 26.78 g a.i./hm²）, T₃（40% pyroxasulfone suspension agent and 51% flumioxazin wettable powder 150 + 22.95 g a.i./hm²）, T₄（40% pyroxasulfone suspension agent 180 g a.i./hm²）, and T₅（51% flumioxazin wettable powder 30.60 g a.i./hm²）, and the clear water was used as the blank control. The results showed that the control efficacy of T₁ treatment were good on Gramineae, broadleaf and Cyperaceae weeds, and the total plant control efficacy and fresh weight control efficacy was 88.62% and 90.01% at 50 days after treatment, respectively, which was better than the other two herbicide mixture and the single treatment. There was no effect on the growth and development of soybean or maize. The yield of soybean and maize was increased by 18.51% and 20.38%, respectively. T₁ treatment can effectively control weeds in soybean and maize intercropping fields at the dose of 180+30.60 g a.i./hm², which has high crop safety and yield-increasing effects, and can be applied in production.