Earthquakes are an important factor in inducing slope failure and the anti-slide pile is an important slope-control engineering measure. Therefore, the study of the mechanism of the anti-slide pile during earthquake activity has important engineering significance for slope protection. Previously, the action mechanism of the anti-slide pile has been mainly studied under static loads and there is a lack of research regarding the pile's response to earthquake activity. Many factors must be simplified when using the two-dimensional analysis method, which affects the accuracy of the results. Taking a project in Meizhou city, Guangdong province as an example, we used ABAQUS software to establish a three-dimensional model and then analyzed the mechanism of the pile-soil effect under earthquake activity. The results show the following:(1) Under earthquake activity, the horizontal displacement of the upper part of the slope is relatively large, with a maximum value of 87.05 mm. (2) Under earthquake load, the stress on the anti-slide pile is far greater than that prior to the earthquake:the maximum value under static loads is 147.24 kPa, and the maximum value of the pile body during an earthquake can reach 326.36 kPa. (3) The strain on the anti-slide pile during an earthquake is much larger than that under static loads:The maximum strain under static loads is 4.63×10^-5 and the maximum strain of the pile during an earthquake is 34.10×10^-5. Therefore, in practical projects, the strength and stiffness of the pile should be taken into account to determine the need for reinforcement of anti-slide piles subjected to earthquake activity. These research conclusions have direct significance on the prevention and control practices adopted in slope engineering projects.