Pressure and flame sensors and laser schlieren system were installed in a mesoscale shock tube to study the flow field evolution near the gas explosion barriers within a confined space.Those Barriers with a blocking rate of 21.56% were set at the glass window.By changing the number of barriers, the flame propagation, pressure change, shock wave movement and flow field change under different working conditions were compared to analyze the influence of barriers on the evolution of gas explosion flow field in confined space.The experimental results show that the excitation effect of barriers on gas explosion cannot be ignored.The maximum explosion overpressure increases by 32.3% and the maximum flame propagation speed increased by 115.4% when a single obstacle is added.In addition, the excitation effect of barriers on gas explosion is positively correlated with the number of barriers and mainly in the area around the barriers.The main mechanism of the excitation effect is that the presence of barriers increases the turbulence intensity near them, which induces the flame tensile deformation, increases the flame front area, and accelerates the chemical reaction.