With the continuous development of musculoskeletal ultrasound,ultrasound diagnosis of inflammatory arthri tis,especially early diagnosis had an increasing important role.Psoriatic arthritis (PsA) was a kind of inflammatory arthritis,which was closely related with psoriasis.It could involve the whole body's large and small joints,especially peripheral joints (often asymmetric),sacroiliac joint and spine.The course of PsA was protracted and easy to recur.Clinical and ima ging manifestations of PsA are similar to rheumatoid arthritis (RA),and need to identify diagnosis.The diagnosis and antidiastole in musculoskeletal ultrasound of PsA were reviewed in this article.