A parameter adjustment method, applied to an electronic device, the electronic device comprising a front camera and a display screen, and the parameter adjustment method comprising: obtaining, when the display screen displays data, an image captured by the front camera that runs based on an initial exposure parameter in response to a first instruction, the initial exposure parameter matching an ambient light brightness; determining (S1202b) a standard brightness by using the ambient light brightness; determining (S1202c) a preset threshold by using the ambient light brightness; calculating an image brightness of the image by using image data of the image; and adjusting the initial exposure parameter of the front camera based on a difference between the image brightness of the image and the standard brightness, to obtain an exposure parameter adjustment value, the exposure parameter adjustment value being used by the front camera to run based on the exposure parameter adjustment value in response to a second instruction, to capture a new image; determining a confidence level for the new image according to a comparison result of the image data of the new image with a sample feature library including feature data of an image in which human eyes gaze at the display screen, the confidence level being used for representing a probability at which human eyes in the image gaze at the display screen; and controlling, if the confidence level of the new image is not less than a preset threshold the display screen not to be turned off and controlling, if the confidence levels of the images (11..15) captured by the front camera within a preset period of time are all less than the preset threshold, the display screen to be turned off. obtaining, when the display screen displays data, an image captured by the front camera that runs based on an initial exposure parameter in response to a first instruction, the initial exposure parameter matching an ambient light brightness; determining (S1202b) a standard brightness by using the ambient light brightness; determining (S1202c) a preset threshold by using the ambient light brightness; calculating an image brightness of the image by using image data of the image; and adjusting the initial exposure parameter of the front camera based on a difference between the image brightness of the image and the standard brightness, to obtain an exposure parameter adjustment value, the exposure parameter adjustment value being used by the front camera to run based on the exposure parameter adjustment value in response to a second instruction, to capture a new image; determining a confidence level for the new image according to a comparison result of the image data of the new image with a sample feature library including feature data of an image in which human eyes gaze at the display screen, the confidence level being used for representing a probability at which human eyes in the image gaze at the display screen; and controlling, if the confidence level of the new image is not less than a preset threshold the display screen not to be turned off and controlling, if the confidence levels of the images (11..15) captured by the front camera within a preset period of time are all less than the preset threshold, the display screen to be turned off.