A novel display system is provided. The display system includes a display portion and a control portion. The control portion includes a controller and a memory device. The display portion has a function of displaying an image. The controller has a function of outputting a signal for controlling a refresh rate of the image. The memory device has a function of storing data including data indicatinga recognition state of the image and data on whether a flicker is recognized in the recognition state by a user or not. The controller has a function of changing the refresh rate of the image with reference to the data stored in the memory device when data on whether a flicker is recognized or not is input by the user.