Electrical stimulation technology has been widely applied in fields such as stroke, Parkinson’s disease, chronic pain and neurorehabilitation. However, the limitations of in vivo electric field detection technology hinder the refined research on its electrophysiological mechanism and further technological upgrades. Based on the finite element method (FEM), high-resolution biophysical models can be constructed, providing a transformative tool for analyzing the mechanism of electrical stimulation and optimizing stimulation parameters. This review systematically summarizes the latest research progress of various types of electrical stimulation based on FEM (including deep brain stimulation (DBS), spinal cord stimulation (SCS), transcranial direct current stimulation (tDCS), and transcutaneous electrical nerve stimulation (TENS)) in the analysis of disease mechanisms, optimization of equipment parameters, and individualized treatment design.