The present invention provides a display system and a diagnostic method. The display system includes an information preprocessing module, a display panel and a control circuit electrically connected to the display panel. The information preprocessing module is used for starting the control circuit and the display panel. The control circuit is used for controlling the display panel to display an image. The information preprocessing module includes a sensor used for collecting physiological information of human body and a preprocessing circuit used for preprocessing the physiological information of human body collected by the sensor and transmitting the preprocessed physiological information of human body to the control circuit. The control circuit is used for receiving and diagnosing the preprocessed physiological information of human body to obtain a diagnosis result. The display panel is used for displaying the diagnosis result.
