The invention discloses a service processing method and system for a wireless body area network (WBAN). According to the method, binary tree networking is carried out on all sensor nodes and a center management node of the WBAN, and the center management node is the vertex of the network; the method comprises the steps that time slot allocation of the sensor nodes is carried out according to network distribution; when emergent service occurs, the sensor nodes with the emergent service occurring broadcast awakening signals to trigger all the sensor nodes to enter an emergent communication state, and the sensor nodes in the normal communication state abandon a current time slot; the sensor nodes with the emergent service and father nodes of an upper layer to which the sensor nodes directly belong sequentially take over the current time slot to the time slot for finishing the emergent service from low to high from a network layer to carry out emergent service processing. Time slot allocation is carried out on the WBAN nodes according to the binary tree network distribution, and the awakening signals trigger all the nodes to enter the emergent communication state; the nodes with the emergent service occurring and the father nodes to which the nodes belong take over the current time slot to the time slot for finishing the emergency service to carry out emergency service processing.