Abstract: To improve the spatial resolution of medical ultrasound imaging, a bemforming method which combines the eigenspace-based minimum variance (ESBMV) with sign coherence factor (SCF) is proposed. Firstly, minimum variance beamforming is used to obtain covariance matrix and weight vector; then the weight vector is projected onto the signal subspace constructed from the eigenstructure of covariance matrix; finally, sign coherence factor is computed and used to optimize echo data obtained from ESBMV. Simulations of point scatterers and cyst phantom and in vivo experiments based on point scatterers and common artery are used to verify the proposed method. The results show that the proposed method is better than delay and sum (DAS), the minimum variance (MV), ESBMV, and ESBMV combined with coherence factor (ESBMV+CF) beamformer in the aspect of resolution, contrast and robustness.