The development of vehicle control network is a difficult problem at present. Because it needs a lot of cheap toolchains,which must meet the requirement of hardware/software co-design. In the toolchains, hardware emulator plays an important role. The emulator provides funcation verification for the development of software and shortens the development period of embedded system. For the development of vehicle control network, this paper proposes an emulator based on QEMU and virtual local area network at the same time introduces a way of building CAN bus network by the emulator. It’s called CES and achieves the function simulation of the hardware environment of the CAN bus network node.