From the cybernetics point of view and using analogy study, the paper analyses the global economic system, discusses its configuration and decomposition, control structure, monitoring and management objectives for different levels, information structure, control strategy as well as subsystem control and coordination. This paper theoretically characterizes the economic system crisis as the instability of man-made control system, and applies the relation between stability of engineering large-scale system and that of its subsystems to analogically study the global economic system crisis and obtains five arguments. Economic interpretation to the mixed coordination method is given. And its characteristics, advantages and significance to the mixed economy regulation are clarified. Finally based on above study the paper lists the lessons drawn from the crisis.