The Tanlu fault zone is an important geotectonic belt and seismic activity belt in eastern China. The seismic activity and the risk of strong earthquakes at the junction of Jiangsu and Shandong provinces have been drawing much attention. The occurrence of tectonic earthquakes mainly lies in the geological tectonic movement, which is the contradiction between the in situ stress caused by this movement in the rock formation and the rock resistance. The earthquake is the result of the intensification of this contradiction. Applying the hydraulic fracturing method, a borehole insitu stress measurement was carried out in this area. At the same time, referring to the data of insitu stress in the depth of 301~5047m of the main hole of the Chinese scientific drilling obtained by the predecessors using the method of borehole caving and acoustic emission, the insitu stress state in the study area is revealed. Coulomb Criterion and Byerlee's law and the fault friction parameters were used to analyze the accumulation of in situ stress and the possibility of fault slip in this area. In the preliminary results, hydraulic fracturing method is used to obtain the measuring points of Xinwangzhuang village in donghai county, jiangsu province that the magnitude of the measured maximum horizontal principal stress and minimum horizontal principal stress are 4. 02~19. 40MPa and 3. 68~13. 51MPa respectively in the depth range of 75. 74~191. 04m. The measured value of the minimum horizontal principal stress at Maozhuang Village, Donghai County, Jiangsu Province, obtained by the method of borehole caving, is 25. 3~122. 0MPa and the maximum horizontal principal stress is 41. 4~166. 4MPa at the depth of 1069~5047m. σH>σh>σv is the stress state of reverse fault in the range of 660 meters above the earth’s surface, and σH>σv>σh below 660 meters, which is the state of earth stress of strikeslip fault. Comprehensive analysis shows that the accumulation of insitu stress in the study area is not high, and the fault slip is unlikely.