In order to improve the transmission quality of video streams in multi-channel wireless multihop networks,a distributed cross-layer optimization algorithm is presented.In this algorithm,first,the channel allocation,interference,bandwidth allocation,delay allocation and video stream distrotion are all modeled.Then,based on the convex programming and the theory of Lagrangian dual decomposition,the total distortion of the video streams under end-to-end delay constraints is minimized by adjusting the source coding rate,the link bandwidth,the upper average link delay and the radio-frequency and channel allocation.Theoretical analyses and numerical simulations show that the proposed distributed algorithm can converge to the global optimum.