The main purpose of this paper is to conduct the critical technologies and design procedures of a versatile software platform for Taiwan's electric vans established by Industrial Technology Research Institute (ITRI), Taiwan. To raise the development efficiency and to reduce the cost, a Matlab/Simulink-coded software, named "E-Van-Sim", was designed for the purpose of evaluating the vehicle/subsystem performance and for preliminarily studying prototype vehicle control strategies. By adopting forward/backward simulation approach, E-Van-Sim is able to accommodate both the realtime simulation and the high model accuracy. It consists of subsystems (key components) such as the traction motors, lithium batteries, high-power transformers (DC/DC converter, charger, etc.), auxiliary components, transmission, and longitudinal vehicle dynamics. The modules of drive behaviour, standard testing cycles and vehicle control strategy were also integrated. This study demonstrates the results of vehicle/subsystem dynamics, energy consumption and energy recovery, and vehicle control rules (operation modes) under specific driving cycles. It proves that the effective research is accessible by using the developed E-Van-Sim. An on-line version of E-Van-Sim will be established in order to complete the Hardware-in-the-Loop (HIL) platform in the near future.