A purpose of the present invention is providing a cognitive radio network frequency spectrum sharing method based on feedback control information. The method is characterized in that: initializing a communication transmission parameter in a cognitive radio network, according to interruption probability restriction approximation equivalence of an authorized user, obtaining interruption probabilityrestriction conditions of different cognitive users, and initializing each cognitive user power; observing interruption times n of the authorized user in time t, updating an estimated observation interruption probability, updating an adjusting factor, calculating an improved power distribution strategy, detecting whether a cycle termination condition is satisfied or not, if not, returning to the above step, if so, ending steps. According to the invention, an optimization theory and feedback control information of the authorized user are utilized to establish a cognitive radio network frequency spectrum sharing model, interruption probability of authorized user communication is ensured to be lower than a preset level, the authorized user is facilitated to iteratively solve a self power distribution strategy through observation of the feedback control information of the authorized user.