The invention discloses a construction method of optimized active disturbance rejection controllers of a bearing-less permanent magnet motor suspension system. The construction method comprises the following steps of constructing second-order extended state observers in an x direction and a y direction according to input and output signals of a composite controlled object, respectively comparing a given displacement signal with outputs fed back by the composite displacements in the x direction and the y direction, and determining input signals of deflection error controllers in the x direction and the y direction; respectively combining the output signals of the second-order extended state observers in the x direction and the y direction with the output signals of the deflection error controllers in the x direction and the y direction so as to obtain a given input of the composite controlled object; and constructing the optimized active disturbance rejection controllers in the x direction and the y direction so as to control the composite controlled object together. The construction method, provided by the invention, requires fewer parameters to be adjusted, the steady state response performance and the dynamic response performance of the system are both considered, characteristics of the system under no-load, on-load and load sudden change suspension operation work conditions are considered, and an algorithm has very good adaptability.