Backlight source control circuit and display terminal

The invention belongs to the field of backlight source control and discloses a backlight source control circuit and a display terminal. In the embodiment, voltage division is performed on a working voltage output by a power supply module according to a preset voltage division ratio by virtue of a reference voltage source, so that a reference voltage is output; the voltage division ratio is adjusted according to the light intensity of an external environment by virtue of a photosensor, and voltage division is performed on the working voltage according to the voltage division ratio so as to correspondingly output a photoinduction voltage; the photoinduction voltage is compared with the reference voltage by virtue of an operational amplifier chip, and the brightness of a backlight source is correspondingly controlled according to the comparison result. The backlight source control circuit provided by the embodiment of the invention is simple in design and high in efficiency and can be used for improving the user experience of users.