The present application provides an automatic gain control method and device, a terminal, and a storage medium. The method comprises: obtaining a first received power at which a terminal receives a first signal, and the transmit power deviation between the first signal and a preset signal; and adjusting a gain value of the terminal according to the first received power, the transmit power deviation, and a preset received power of the preset signal. In this way, the fluctuation of gain adjustment is reduced, and the downlink performance loss is avoided.