The Xiangyangping uranium ore deposit is a new-found deposit in Miaoershan ore field for the past few years. Chloritization is one of the most important alteration types and prospecting indicators in the Xiangyangping uranium deposit. Based on the detailed field and interior petrographic observation for the ore samples in the Xiang-yangping uranium deposit, electron probe microanalyzer (EPMA) is employed to study paragenetic association characteristics and morphological features of chlorites. Chemical compositions of chlorites could help to confirm the chemical types of chlorites and formation condition of chlorites, and finally to discuss their formation mechanism and the relationship with uranium mineralization. The chlorites in the Xiangyangping uranium ore deposit could be divided into four types, including biotite-alteration type, fracture-filling type, uranium-associated types and clay minerals transformed types. The Fe-Si diagram has revealed that the chlorites are mainly brunsvigite area, partly ripidolite and few pycnochlorite, respectively. The formation temperature range of chlorite is 190~265℃ (averagely 239℃), which belong to the mesothermal epithermal alteration. The formation mechanism is dissolution-crystallization and dissolution-migration-crystallization. The chloritization provided the environment for uranium mineralization, and promoted the activation, migration and deposition of uranium.