The invention discloses an autodiagnosis system and an autodiagnosis method for an intelligent controller and relates to the technical field of fault diagnosis. The autodiagnosis system of the intelligent controller comprises an autodiagnosis module used for detecting faults of the intelligent controller, a display module and an operation module. The display module is connected with the autodiagnosis module and used for receiving a detection result of the autodiagnosis module and displaying the detection result. The operation module is used for controlling the diagnosis state of the autodiagnosis module and a display page of the display module. The invention further provides the autodiagnosis method for the intelligent controller. By means of the autodiagnosis system and the autodiagnosis method, autodiagnosis of the intelligent controller can be achieved, an operator can direct find a fault point conveniently, the fault can be quickly and effectively removed, the working efficiency of maintenance personnel is improved, and the intelligentization level of the intelligent controller is improved.