Gypsum rock is widely used in engineering and has special physical and chemical properties, which often cause engineering problems. Therefore, it is especially important to study the dissolution characteristics of gypsum rock and its properties such as strength, plasticity and brittleness before and after dissolution. In this paper, the dissolution mechanism is analyzed by indoor dissolution test. The microstructure is observed by electron microscopy, the strength deterioration mechanism is analyzed, and the softening properties of gypsum rock under different solution conditions are studied by uniaxial compression test. The results show that different solutions have different effects on gypsum rock. The gypsum rock is immersed in pure water as reference. The NaCl solution promotes the dissolution of gypsum rock. The strength is greatly reduced, which is about one third of the strength of pure water. The plasticity becomes stronger and the brittleness is weakened; The glacial acetic acid solution reduces the amount of dissolution of gypsum rock, the strength increases slightly, the plasticity becomes weak, and the brittleness becomes stronger; the sodium hydroxide solution can react with the gypsum rock to form calcium hydroxide, so in the early stage It can promote the dissolution of gypsum rock, and the later formation of more calcium hydroxide complex attached to the surface of the rock sample prevents the gypsum rock from being dissolved and the strength becomes larger and the plasticity becomes stronger. Microscopic electron micrographs show that the dissolution of gypsum rock by different solutions is most serious with sodium chloride solution, followed by pure water, glacial acetic acid solution and sodium hydroxide solution. The intensity of the acoustic emission activity is consistent with the amount of erosion.