Abstract: To improve the range resolution capability of active sonar to the target echo highlight,based on rangedimensional beamforming method a modified weighted adaptive high-resolution range estimation method is proposed.We give three types of weight matrix.The first type of weight matrix is a diagonal matrix whose first diagonal element is the residual and the rest are zero.The second type of weight matrix is the identity matrix.The third type of matrix is the diagonal matrix of residuals.Use high-order linear prediction model with different reference sub-bands to construct power spectrum expression.The proposed method avoids the low-order linear prediction model in rangedimensional beamforming method.Compare the proposed method with the range-dimensional beamforming method through numerical simulation and tank test.The results show that the proposed method obtains better range resolution under almost the same amount of calculation.