Objective:To investigate COVID-19 vaccination status and relevant adverse reactions in patients with psoriasis treated with biological agents, and to explore the effect of COVID-19 vaccination on psoriatic lesions.Methods:Clinical data were collected from 572 psoriasis patients aged 18 - 60 years, who were registered in the management system of psoriasis patients treated with biological agents in the University of Hong Kong-Shenzhen Hospital from May 2019 to June 2021. The COVID-19 vaccination status was investigated by telephone interviews, and the vaccination-related information was obtained by fixed healthcare workers during a fixed time period according to a predesigned questionnaire. Measurement data were compared between two groups by using t test, and enumeration data were compared by using chi-square test or Fisher′s exact test. Results:The COVID-19 vaccination coverage rate was 43.13% (226 cases) among the 524 patients who completed the telephone interview, and was significantly lower in the biological agent treatment group (30.79%, 105/341) than in the traditional drug treatment group (66.12%, 121/183; χ2 = 60.60, P < 0.001) . The main reason for not being vaccinated was patients′ fear of vaccine safety (49.66%, 148/298) , followed by doctors′ not recommending (26.51%, 79/298) . In the biological agent treatment group after vaccination, the exacerbation of psoriatic lesions was more common in patients receiving prolonged-interval treatment (42.86%, 6/14) compared with those receiving regular treatment (4.40%, 4/91; Fisher′s exact test, P < 0.001) . Skin lesions were severely aggravated in two patients after COVID-19 vaccination, who ever experienced allergic reactions and whose skin lesions did not completely subside after the treatment with biological agents. Conclusions:The COVID-19 vaccination coverage rate was relatively low in the psoriasis patients treated with biological agents, and no serious adverse reaction was observed after vaccination. Prolonged-interval treatment due to COVID-19 vaccination ran the risk of exacerbation of skin lesions.