Disclosed is a control method for controlling data return and energy optimization in a passive sensor network. The passive sensor network comprises an aggregation node and sensor nodes. The control method comprises an energy calculating step, an energy broadcasting step, an energy collecting step, a clustering step and a data transmitting step. By means of the control method in the embodiments of the present disclosure, data return and energy optimization in a passive sensor network are controlled, so that insofar as all sensor nodes can return data to an aggregation node, the aggregation node consumes the least amount of energy, thereby achieving the optimal energy usage efficiency. Also disclosed is a control device.