Abstract: Estimating exactly DOA (Direction of Arrival) of underwater noise source confuses the assayer of passive sonar target. A high-resolution DOA algorithm is presented,which concerns the performance of TCT (Two-sided Correlation matrices Transformation) in estimating DOA (Direction of Arrival) of underwater noise source of single-target. The high-frequency group of underwater wideband noise is selected to estimate DOA. The maximum power frequency in the selected frequency group is used for the estimation of initial DOA. Computer simulation results and experimental results with real underwater acoustic data have confirmed the algorithm is high-resolution and lower computational cost. The algorithm makes sure of ranging underwater moving targets by two sonar array.