γ-Cu2(OH)3Cl is one of the isomers of copper hydroxychloride, which exists widely in nature. It can not only be used as biological copper nutrient additives, but also has exotic magnetic properties. Clinoatacamite (γ-Cu2(OH)3Cl) was prepared via a hydrothermal synthesis strategy. The Raman scattering spectroscopy test was first carried out under atmospheric pressure, and the frequencies were divided into low frequency region and medium frequency region, respectively. The spectral bands were attributable and divided in detail. The lattice vibrations and crystal structure evolution behavior of γ-Cu2(OH)3Cl under high pressure were studied by using in-situ high-pressure Raman scattering spectroscopy technique, and the maximum pressure reached 17.8 GPa. The changes of Raman vibration modes with pressure were studied, and the red shift phenomenon is analyzed and explained. The results of this study may provide fundamental spectroscopic theory and basic data in the calibration of copper nutrient additives.