The invention aims to provide a fiber cooking, defibrating and drying system which can effectively save energy and has a good fiber drying effect. The fiber cooking, defibrating and drying system comprises a wood chip cooker, a defibrator, a dryer and a fiber and steam separation device, wherein the wood chip cooker is provided with a wood chip input pipe and a steam input pipe; the fiber and steam separation device is provided with a feeding pipe, a steam outlet pipe and a fiber outlet pipe; the wood chip cooker, the defibrator, the feeding pipe of the fiber and steam separation device, the fiber outlet pipe of the fiber and steam separation device and the dryer are connected in series sequentially, and the steam outlet pipe of the fiber and steam separation device is connected with the steam inlet pipe of the wood chip cooker.