In this paper, MPTCP multi-path transmission technology based on adaptive congestion control is studied to improve network performance. Firstly, the basic principle of MPTCP and its advantages in multi-path data transmission are introduced. Secondly, an innovative adaptive congestion control method is proposed to optimize the performance of MPTCP by dynamically adjusting path weights and feedback-based flow control strategy. To verify the effectiveness of this method, a simulation environment for multi-path transmission is constructed using NS-3 and experiments are carried out.The experimental results show that adaptive MPTCP outperforms traditional TCP methods in key indicators such as throughput, delay and packet loss rate, providing an effective reference for the optimization of network transmission technology.