The embodiments of the present disclosure are applicable to the technical field of computer science and application technology, and disclose a wireless body area network, a key generation method and a key distribution method in the wireless body area network, and a related device. The gait acceleration signal is extracted synchronously through the respective acceleration acquisition devices integrated with the coordinator and the wearable equipment, the position information corresponding to the peak value and the valley value in the gait acceleration signal is correspondingly extracted and is taken as the gait common information, and the gait common information is used to perform key distribution in the wireless body area network, the security and the consistency are higher, the calculation is simplified, the key distribution method is suitable for wearable devices having limited resources.