INTRODUCTION A number of studies have reported a high correlation between psoriasis and metabolic syndrome (MetS), and tobacco smoking is one independent risk factor accounting for the increased prevalence both for psoriasis and MetS. However, few studies have been conducted to assess the effects of tobacco smoking on co-morbidities of psoriasis and MetS. METHODS We conducted a cross-sectional study with 1014 psoriasis patients recruited from January to May 2021. Patients were recruited with a cluster survey method in Yueyang Hospital (affiliated with Shanghai University of Traditional Chinese Medicine) and Shanghai Skin Diseases Hospital (affiliated with Tongji University). Data were collected by face-to-face questionnaire interviews which included basic information, personal life habits, medical history, and clinical examinations. SPSS 24.0 was used for data analysis and a p<0.05 was considered statistically significant. RESULTS The 1014 psoriasis patients were predominantly males (65.58%), with an average age of 45.98 years (IQR: 34.00-57.00). Of these, 25.74% (261) of psoriasis had MetS and 31.85% (323) were tobacco smokers. Male psoriasis patients had higher tobacco smoking prevalence than female patients. With increasing age and BMI, the prevalence of tobacco smoking among psoriasis patients increased dramatically (p<0.01). Logistic regression indicated that psoriasis patients with tobacco smoking had 1.78 times (95% CI: 1.21-2.60) the probability to have MetS than those without tobacco smoking, even adjusting for potential confounding factors. Moreover, smoking psoriasis patients with MetS consumed more cigarettes per day, with longer smoking duration, but with an older age of smoking initiation. CONCLUSIONS The prevalence of tobacco smoking and MetS among psoriasis patients was high in Shanghai, and tobacco smoking was positively associated with the MetS among psoriasis patients. Clinicians should recommend psoriasis patients to abstain from tobacco smoking and provide tobacco cessation assistance regularly.