Abstract: The processes of slow positron beam implantation into metals were studied by employing the Geant4 software. The backscattering coefficients of two patterns (i.e. normal incidence and oblique incidence) were calculated, and the distribution curves of positron implantation depth at oblique incidence and the relations between the backscattering coefficient and the incident angle were obtained. Further analysis of lateral diffusions of positrons at different angles was conducted. Simulations indicate that the lateral diffusions of slow positrons become more significant obliquely implanting into metals with smaller atomic numbers. The simulation can provide some useful referential data for the research of metals using slow positron beam technology.