Abstract: In this paper, a mathematical model of unsteady heat transfer of PV/T collector was established. After verifying the reliability of the model through the measured data of the existing experimental platform, the water-cooled PV/T collector and the air/water dualchannel PV/T collector were tested. On this basis, the performance of the dual-channel PV/T collector was optimized from the perspective of operating parameters. The results show that under the winter conditions in Taiyuan, when the water mass flow is 0.01 kg/s,the performance of the PV/T collector after adding the air channel is better than that of the water-cooled PV/T collector. The overall efficiency of the device is improved by about 0.84%. When the air mass flow is constant, as the water flow increases from 0.01 kg/s to0.09 kg/s,the comprehensive performance efficiency of the dual-channel PV/T collector increases by about 9.22%. When the water mass flow is greater than 0.03 kg/s,increasing the air mass flow will weaken the overall performance of the dual-channel PV/T collector. After comprehensive consideration, the paper suggests that the water flow rate of the dual-channel PV/T collector should not be greater than0.03 kg/s in winter conditions in Taiyuan.