This study is to investigate the prevalence of subclinical enthesitis and synovitis with PDUS in patients with psoriasis, and identify the risk factors. There were 30 patients with plaque psoriasis and 20 age-matched controls with other skin disease in this study. All patients without arthritis underwent dermatological assessment and PDUS examination. The frequency of US synovitis was higher in psoriasis compared to control (5/30 vs 0/20, P= 0.149). But US enthesitis was not found in two groups. Among demographic and clinical data, predictors for US synovitis included first-degree family history of psoriasis [odds ratio (OR) 17.250; 95% CI 1.730, 172.015; P= 0.015] and nail involvement (OR21; 95% CI 1.834, 240.508; P= 0.014). The prevalence of subclinical synovitis and enthesitis in Chinese patients with psoriasis was low. First-degree family history of psoriasis, nail involvement may be the risk factors for subclinical synovitis and enthesitis.