The embodiment of the utility model provides a circulating fluidized bed gasification furnace. The circulating fluidized bed gasification furnace comprises a start-up burner which comprises a burner nozzle, an outer sleeve and an ignition device, wherein the outer sleeve sleeves the first end of the burner nozzle; the ignition end of the ignition device is close to a port of the first end of the burner nozzle; and the start-up burner is fixedly connected to the inside of a primary air duct of the circulating fluidized bed gasification furnace. According to the embodiment of the utility model, the primary air duct is used as a gas pipeline of the start-up burner, and primary air is used as combustion-supporting air to provide furnace ignition hot air for the circulating fluidized bed gasification furnace, so that an ignition process is simplified, the ignition reliability is improved, the start-up burner does not need an additional high-pressure blower, and then the overall cost of the circulating fluidized bed gasification furnace is reduced.