By　adding　bilateral　elevated　layers,　the　renovation　and　expansion　of　the　expressway　have　improved　the　traffic　capacity,　but　a　subsequent　rise　in　problems,　such　as　insufficient　spacing,　excessive　traffic　volume,　and　multi-diversion,　has　made　the　existing　traffic　signs　fail　to　meet　the　driversǵuidance　needs.　In　response　to　this　issue,　this　study　took　the　Ji-He　Expressway　in　Shenzhen　as　an　example　and　designed　four　optimized　traffic　sign　schemes　of　interchange　based　on　the　conventional　standard　scheme,　and　developed　the　corresponding　stereoscopic　compound　expressway　scenes　by　the　Unity3D　engine.　The　vehicles　on　the　expressway　will　drive　out　of　the　ground-level　road　at　the　first　diversion,　enter　the　elevated-level　road　at　the　second　diversion,　and　connect　to　other　expressways　at　the　third　diversion.　28　drivers　simulated　driving　in　different　scenes　using　external　interactive　devices,　and　their　driving　behavior　data　such　as　speed,　acceleration,　lane　position,　etc.,　were　obtained.　By　calculating　the　point-by-point　significance　of　indicators　within　each　affected　section　in　different　guidance　sign　design　schemes,　differences　in　spatial　dimensions　of　each　indicator　were　presented,　and　further　analysis　shows　that　3　km　warning　signs　can　help　drivers　perceive　the　situation　of　the　ramp　ahead　as　early　as　possible.　Lane　guidance　signs　can　improve　the　longitudinal　and　lateral　stability　of　vehicles　at　the　ramp,　and　drivers　can　take　better　lane　changing　strategies.　Navigation　voices　assistance　can　improve　the　driverś　speed　control　proficiency,　lane　changing　awareness　of　expressway　exits,　and　psychological　comfort　at　the　interchange　of　stereoscopic　compound　expressway.　The　research　shows　that　Unity3D　has　high　fidelity,　good　interactivity,　and　low　cost,　and　it　can　provide　technical　support　for　relevant　research　on　driving　behavior　in　complex　road　scenes　in　the　future.　At　the　same　time,　this　study　also　provides　a　theoretical　reference　for　the　establishment　of　traffic　guidance　signs　in　expressway　renovation　and　expansion　projects.　©　2024　South　China　University　of　Technology.　All　rights　reserved.