Objective To observe the value of ultrasound vector flow imaging(VFI)combined with singular value decomposition(SVD)filtering for depicting deep microvasculature flow velocity of liver.Methods Grayscale ultrasound,CDFI and contrast-enhanced ultrasound(CEUS)were prospectively performed in a patient with suspected liver hemangioma.Images of CEUS were dealt with SVD filtering.Cross-correlation algorithm was used to obtain images of VFI based on grayscale ultrasound,original CEUS and SVD filtered CEUS,respectively,and the ability of the above images for depicting liver microvascular flow direction and velocity were compared.Results The signal-to-noise ratio(SNR)of liver grayscale ultrasound,original CEUS and SVD filtered CEUS images was 7.56,17.65 and 22.43 dB,respectively,while their contrast-to-issue ratio(CTR)was 1.12,7.56 and 16.34 dB,respectively.Compared with VFI based on grayscale ultrasound and original CEUS,VFI based on SVD filtered CEUS could display faster velocity and more uniform direction of blood flow.Before and after SVD filtering,liver microvascular flow velocity measured with VFI was 1.91(0.81,4.11)and 6.83(4.25,9.41)mm/s,respectively,which were significantly different(Z=-10.671,P＜0.001).Conclusion Combined with SVD filtering could significantly improve the efficiency of VFI for depicting liver deep microvasculature flow velocity.