Main control unit with control method based on CAN bus for pure electric automobile comprises modules of micro controller, analog variable and switching value conditioning, instrument drive, relay drive, CAN bus interface of high and low speed, memory unit, information storage, power source, and communication interface. The main control unit manages, coordinate and monitor all sectors of vehicle dynamic chain to improve energy utilization efficiency and ensure safety and reliability. It collects drive signal of driver, obtains motor and battery system information through CAN bus, takes analysis and calculation; sends motor control and battery manage command by Can bus, and realizes drive control, energy optimization control and brake feedback control for whole vehicle. It can also shows state information of whole vehicle, has perfect fault diagnosis and process function and management function for whole gateway and network.