Abstract: As for the problem of congestion control in Transmission Control Protocol（TCP） networks，a sliding mode congestion control scheme is proposed.Based on the TCP networks congestion control model，an asymptotically stable sliding surface is designed by Linear Matrix Inequality（LMI）.The sliding surface can compensate for the effect of the uncertainties in TCP networks.In addition，an improved reaching condition is proposed in order to constrain oscillation of the queue length in router.Simulations are done in different scenarios.The results show that the proposed scheme has better stability and robustness than common sliding mode congestion control scheme.