In order to study the effect of wind barrier porosity on coupled vibration of train-bridge system of heavy haul railway in crosswind, the coupled vibration equation of train-bridge system under wind load was established according to the principle of constant total potential energy of elastic system. The aerodynamic three-component force coefficients and the dynamic responses of train-bridge system were calculated when trains pass through a simply supported T-beam bridge with different pored wind barriers in crosswind. The research results show that with the increase of wind barrier porosity, the drag coefficient of trains increases and the drag coefficient of bridge decreases. The vertical displacement of the bridge is not sensitive to changes in the wind barrier porosity, and the lateral displacement of the bridge increases slightly with the increase of wind barrier porosity. The derailment coefficient and wheel unloading rate of locomotive increase with the increase of wind barrier porosity. When the wind barrier porosity is 30%, the lateral swaying force of full-load trains reaches the minimum. When the wind barrier porosity is 20%, the lateral swaying force of no-load trains reaches the minimum.