The spectrum allocation for links in multi-hop cognitive radio networks is addressed.The links rent the vacant licensed bands offered by primary users for implementing directional transmission.To minimize the individual cost,the links share the licensed band and rental fee.An interference model for the directional transmission in cognitive radio networks is proposed to formulate the cooperative and dynamic behavior of the links using the theory of hedonic game,called spectrum allocation game.The game is proved to converge to the core stable state indicating that all links satisfy with their current conditions and do not deviate from their coalitions.Numerical results show that the game improves spectral efficiency and contributes to reducing the individual cost of the links. The spectrum allocation for links in multi-hop cognitive radio networks is addressed. The rent for the vacant licensed radio networks is addressed. The rent is available for primary users for implementing directional transmission. Minimize the individual costs, the links share the licensed band and rental fee. An interference model for the directional transmission in cognitive radio networks is proposed to formulate the cooperative and dynamic behavior of the links using the theory of hedonic game, called spectrum allocation game. The game is proved to converge to the core stable state indicating that all with satisfy their current conditions and do not deviate from their coalitions. Numerical results show that the game improves spectral efficiency and contributes to reducing the individual cost of the links.