Abstract: A novel passive radar imaging time-domain algorithm is presented based on single-frequency continuous wave. The signal matched matrix is builded firstly, and the echo signal is expanded into a echo signal matrix. Finally the sum in time dimension of the Hadamard product of the signal matched matrix and the echo signal matrix can be got. Then the echo signal matched integration is implemented and the scattering points are focused. The algorithm resolution and factors of affecting the imaging quality are analyzed. The algorithm is performed in time domain and the interpolation in frequency domain is avoided. Based on the theoretical analysis, simulation experiment confirms the validity of the proposed algorithm.