This paper develops a full three-dimensional PIC/MCC algorithm, and uses it to conduct a full range of numerical diagnosis of the hot JAEA 10A ion source at home and abroad, explores lateral drift and energy distribution of electrons in the electron energy deposition process, analyzes the influence of the main physical parameters on the electronic deposition. Simulation and analysis results show that electronic horizontal shift (-Y direction) comes from the filtering zone of the magnetic drift. Increasing the filtering field, the magnetic drift increases, and lateral drift is aggravated, and the utilization of electronics increases; improving the discharge of chamber pressure, the electronic collision will be more frequent; thereby increasing lateral non-uniformity can improve the utilization of electronics.