The aim of this study was to assess the discriminative utility of nail features detected by B-mode (BM), enhanced flow (eflow) and power Doppler (PD) in patients with psoriasis or nail psoriasis (NP) and healthy controls.Ultrasound appearance of nails was investigated in 5 patients with NP, 8 patients with psoriasis and 7 healthy controls. In total, 195 nails were examined.The thickness of the nail bed (TNB), the thickness of the nail plate (TNP) and the thickness of the nail matrix (TNM) did not differentiate between NP and psoriasis in longitudinal and cross-section of nails. Resistance index (RI) in nails was higher in patients with NP than in patients with psoriasis, and significantly higher in patients with psoriasis than in healthy controls. TNP between patients with psoriasis and healthy controls was statistically insignificant in longitudinal section of nails, but higher than that in the cross-section of nails. TNM was higher in patients with psoriasis than in healthy controls. The ultrasound features of NP in longitudinal and cross-section of nails, nail bed (NB) eflow and PD signal were statistically significant among patients with NP or psoriasis and healthy controls. In patients with NP, there was a correlation between the ultrasound features of NP in longitudinal and cross-section of nails and nail psoriasis severity index (NAPSI).Our study displayed the usefulness of ultrasound nail examinations in psoriatic nails, not only assessing ultrasonic features of nails and proving correlation between ultrasonic features of nails and NAPSI, but also comparing the accuracy of new technology of blood flow signal in nails.