The invention provides a transparent flip smartphone standby power-saving system and a method. The system includes a mobile phone central processing unit (CPU), a microcontroller, a POWER button, a display drive module, a display screen, a transparent flip cover, a low brightness background display module and a high brightness background display module. The display screen is arranged below the transparent flip cover, and the mobile phone CPU is connected with the display drive module through the microcontroller. The display drive module is connected with the display screen through the low brightness background display module and the high brightness background module. The low brightness background display module and the high brightness background display module are utilized to light the display screen in a matched mode respectively according to different operations of users, when the users only need to check the time, a calendar and other operations, the low brightness background display module is correspondingly driven, and the screen is enabled to be in a low power consumption state; when the users need to carry out mobile phone procedure operations, the high brightness background display module is driven, and the screen is enabled to be in a high power consumption state, so that the time and the calendar are convenient to check for the users and the power consumption cannot be increased.