Abstract: Underground coal mines are often disturbed by acidic water corrosion and dynamic loads such as mining and blasting. it is of great significance to study dynamic mechanical behavior of coal based on acid corrosion to ensure the safety of coal mine production. In this study, the split Hopkinson bar (SHPB) system was used to carry out dynamic tensile tests on coal before and after pH= 2,4 acid solution treatment. Based on the X-ray diffraction (XRD) test results, the correlation between the damage mechanism of acidic on coal and mechanical properties was explored. The results show that the dynamic tensile strength of coal displays an apparent rate dependency, but the rate dependency is weakened by acidic corrosion. The stronger the acidic is, the more significant the weakening effect is. At the same loading rate, the relationship between the tensile strength of different coal samples is raw coal > pH=4 > pH=2. After acid corrosion, the dissipated energy and the growth rate of dissipated energy decrease obviously. XRD test shows that damage mechanisms in acid to coal is manifested in its removal of inorganic minerals and small molecule organic matter in coal, which leads to a decrease in the mechanical properties of coal.