Abstract: In cognitive radio network, some factors affect secondary users′ selection of target channel to switch which are its transmission power, fading factor, bandwidth, and channel availability on the authorized channel, etc. In this paper, a spectrum handoff strategy based on dynamic weights′ adjustment is presented, considering the degree of each factor’s importance and dynamics which are not fully considered in multi-attribute decision of spectrum handoff in the past. The proposed method sets the dynamic weights by the change of environment and the subjective experience. Then the value of utility function is obtained by multiple attribute of simple weighted algorithm. The target channel to switch is determined according to its descending order. The simulation results show that the proposed algorithm can reduce the switching times of secondary users, and improve the effective transmission rate of data.