Abstract: Based on the waveform data from digital seismic network of Shandong province and its adjacent regions, this article retrieved the focal mechanism solutions of the Jinan M4.1 Earthquake with the CAP （Cut and Paste Method） method. The results show that the moment magnitude is 4.1, the estimated focal depth is 3.3 km. The strike, dip and slip angles of two nodal planes of the best double couple solution are 219.0°, 57.0°, −156.0° and 115.4°, 70.1°, −35.4°. We infer that the plane Ⅱ was the fault plane with the analysis of the distribution of aftershocks. Both the Changqing fault and the Dong’e fault nearby the epicenter were not the seismogenic fault. Therefore, we assumed that there are one or several buried faults nearby Ji'nan earthquake.