An LED backlight source drive circuit, an LED backlight source and a liquid crystal display device are provided. LED backlight source drive circuit includes a voltage input terminal, a coupling module, and a rectifier module. The coupling module is connected to the voltage input terminal for receiving a current complying with a total working voltage of two power consumption modules from the voltage input terminal, and converting the current into a current complying with a working voltage of one power consumption module. The rectifier module is connected to the coupling module for inputting the current complying with the working voltage of one power consumption module into two serially-connected power consumption modules, thereby supplying power to the power consumption modules. The LED backlight source and the liquid crystal display device include two power consumption modules and the above LED backlight source drive circuit.
展开▼