Abstract: The aichitecture for the Beyond 3rd Generation or 4th Generation wireless nerworks aims at integrating various heterogeneous wireless access networks over an IP backbone. To provide seamless mobility, one of the design issues is the vertical handoff support. In this paper, a SINR (Signal to Interference plus Noise Ratio) and AHP (Analytic Hierarchy Process) based SAW (Simple Additive Weighting) (SASAW) vertical handoff algorithm is proposed, which uses the combined effects of SINR with SINR value from one network being converted to equivalent SINR value to the target network for getting the same data rate, user required bandwidth, user traffic cost and available bandwidth of the participating access networks to construct the attribute matrix and make handoff decisions for multi-attribute QoS consideration according to the features of the traffic. For performance evaluation, four traffic classed defined by 3GPP are considered. The weight relations of decision elements are determined by eigenvalue method of AHP to construct the comparison decision matrix, and then check its Consistency. The weight vector is then produced using the eigenvalue method according to the decision matrix. Finally, SAW algorithm is used to make decision according to the attribute matrix and weight vector. The performance of throughput, dropping probability, user traffic cost and the number of vertical handoff between different vertical handoff decision algorithms are compared. The results show that the proposed scheme can achieve excellent performance according to the characteristics of the traffic by considering the relations of multiple attributions synthetically.