On August 6, 2023, M5. 5 earthquake occurred in Pingyuan County, Dezhou City, Shandong Province, causing significant economic losses and ending the nearly 40- year period of M≥5. 0 seismic quiet in Shandong Province. The epicenter of the Pingyuan earthquake is located in a densely populated area, with rapid economic development. The changes in regional seismicity resulting from this earthquake and the potential for future strong earthquakes are significant social concerns. We use the finite element numerical simulation with a three- dimensional model to study the co- seismic deformation and stress changes in the seismogenic environment at the epicenter and its surroundings. Additionally, we utilize the assumed rupture model to simulate the co- seismic dislocation. Based on the Coulomb stress change theory, we investigate the seismicity changes in the surroundings. The results indicate that the primary deformation caused by the earthquake is concentrated within 10 km of the seismogenic fault, and the Coulomb failure stress at the epicenter decreases by more than 500 kPa. The probability of a strong earthquake occurring is low in the near future. The Pingyuan earthquake has a significant impact on the seismicity in the surroundings. It may increase the occurrence of slip- type small and medium earthquakes in the north, while reducing the occurrence of normal fault- type earthquakes in the west. Longer seismic data and more comprehensive research are still needed to understand the seismicity changes in the North China Plain and its adjacent faults.