Abstract: For the reason that existing construction machinery controllers can not meet the need of performance status monitoring and fault diagnosis,an embedded intelligent controller based on CAN bus is studied.The controller system is mainly based on embedded soft-PLC technology.It adopts embedded real-time operating systemμC/OS-Ⅱas the scheduling core,and takes IEC61131-3 standard PLC run-time system and CANopen protocol stack as the main parts.The new controller not only has the control functions of the traditional PLC controllers,but also has a good capability of network communication, and it is able to meet the need of performance status monitoring and fault diagnosis.A realization method of intelligent controller for construction machinery based on embedded soft-PLC technology is described in detail.