1. College of Earth Sciences, Jilin University, Changchun 130061, China;
2. North China University of Science and Technology, Tangshan 063009, Hebei, China

This study designs three dissolution experiments focusing on the interaction of three kinds of fluid with Bozhong granite in autoclave equipment. The three kinds of fluid include atmospheric water, organic acid (ground water) and organic acids in atmospheric water (ground water). The sample analysis before and after experiment shows that the fluids interact with alkali feldspars and plagioclases which are the major minerals in granite. Different degrees of corrosion, dissolution and secondary action happen to the alkali feldspars and plagioclases at different temperatures. The secondary porosity and secondary minerals such as kaolinite are also formed which increase the surface porosity and the average throat size. There are differences in the weight of samples before and after the reaction, and it is found that the higher the temperature, the smaller the residual weight. The analysis of the three interaction results indicates that the organic acid (ground water) has the most obvious impact on improving the granite reservoir properties compared with the other two kinds of solution.