Abstract: In this paper, the author made investigate in detail to structure joints developed in Later Middle-Pleistocene disclosed on a building site in the south suburb of Hefei area, fillings of the joints each time were collected separately , dated and analyzed, combined with microscopic observation to the fillings. The research result shows there were many groups tectonic joints with obvious relation cut each other during Later Middle-Pleistocene. This shows many times tectonic events had been taken placed in research area. This discovery and understand have significance to a certainty for opening out deformation history and abundance research content to Hefei area during Middle-Late Pleistocene.