The tank is a typical mobile pressure vessel, which plays an important role in the hazardous chemical transportation. Research on the influence of baffle on liquid sloshing have great significance to the design and anti-rolling of tank. In this work, the influence of liquid height, excitation frequency and excitation amplitude on the impact pressure caused by liquid sloshing were studied by experiments on a typical tank model. The shape of free surface and the peak of impact pressure on the tank wall and baffle were investigated. The experimental results show that the natural frequency of the free surface will change with the installation of the baffle, and the excitation frequency of the severe sloshing of the free surface increases after installing the baffle in the tank model. The baffle can effectively reduce the peak of impact pressure under the same excitation frequency and amplitude. Within the excitation frequency range of the test, with half of liquid height, the peak of impact pressure at the free surface of the baffle is higher than the tank wall at the same height; under the condition of high liquid, the peak of impact pressure on the tank wall is more obvious than that on the baffle at the height below the free surface. On the basis of this research, the actual characteristics of the tank and the numerical modelling of liquid sloshing may offer direction for the structural design and optimization of both the tank and baffle.