Ti₃C₂T_x@MnO₂ composites with different morphologies were prepared by liquid-phase coprecipitation and hydrothermal method using Ti₃C₂T_x@PDA as matrix, KMnO₄ as manganese source, CTAB or PEG as surfactant. Effect of MnO₂ morphology (δ-MnO₂ nanofragments, α-MnO₂ nanorods, α-MnO₂ nanoflowers and α-MnO₂ nanowires) on phase structure and electrochemical performance of Ti₃C₂T_x was analyzed by FE-SEM, XRD, Raman, FT-IR, BET, and electrochemical measurements. The results show that Ti₃C₂T_x@α-MnO₂ nanowires possesses better comprehensive electrochemical properties (340.9 F·g ^-1 at 2 mV·s ^-1), nearly 2.5 times higher than using CTAB, and smaller charge transfer resistance, as well as excellent cycle stability.