To improve the quality of ultrasonic coherent plane wave compounding ( CPWC) imaging, a weighting algorithm based on circular statistics vector (CSV) is proposed. In this algorithm, the phase of delayed signal is taken as the circular statistical samples and the coherence factor reflecting the consistency of phase distribution is established through the sample average resultant vector. Furthermore, according to the different number of beamforming and coherence factor construction, the weighting algorithm of total circular statistics vector (tCSV) is proposed. Compared with CPWC, results show that the scattering target resolution and cyst contrast radio of CSV and tCSV are increased by at least 23. 67% and 27. 69% , respectively. And the CNR value is decreased by up to 39. 37% . Compared with the coherence factor (CF) and the sign coherence factor (SCF), the maximum resolution and contrast of CSV and tCSV algorithms are reduced by about 12. 83% and 88. 31% , respectively. However, the ability to suppress background noise and retain the amplitude of target echo wave is better. The CNR value is improved by about 20% , and the image quality is more robust.