IMPORTANCE: Clinical characteristics associated with treatment response to biologics in patients with psoriasis have never been systematically investigated. OBJECTIVE: To evaluate the association between patient clinical characteristics and the effectiveness of biologics in treating psoriasis. DATA SOURCES: PubMed, Embase, and Web of Science were searched from their inception through April 2022. Studies in English language that reported response to biologic treatment at approved doses in patients with psoriasis in relation to their clinical characteristics were included. In addition, eligible studies were identified through a search of the reference lists of the included studies. STUDY SELECTION: We only included studies that reported treatment outcomes as Psoriasis Area and Severity Index (PASI) 75 or PASI 90 after 12, 26, and/or 52 weeks of treatment. Both observational studies and randomized clinical trials (RCTs) were considered. Two independent authors conducted the screening process, and 107 studies were assessed for eligibility. DATA EXTRACTION AND SYNTHESIS: The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines were followed. Relevant data were extracted independently by 2 authors. Data were pooled using random-effects models. RCTs and observational studies were pooled in separate analyses. Data were analyzed from June 1, 2023, to August 1, 2023. MAIN OUTCOMES AND MEASURES: The primary outcome was PASI 90 at 26 weeks (6 months). Before data collection began, an investigation of the association between the main (and secondary) outcomes and several clinical characteristics was planned. RESULTS: Overall, 40 studies with a total of 21 438 patients were included. Older age (odds ratio [OR], 0.99; 95% CI, 0.98-1.00), previous exposure to biologics (OR, 0.44; 95% CI, 0.29-0.67), higher body mass index (BMI) (OR, 0.96; 95% CI, 0.94-0.99), previous smoking (OR, 0.81; 95% CI, 0.67-0.98), and current smoking (OR, 0.78; 95% CI, 0.66-0.91) were negatively associated with achieving PASI 90 at 6 months in observational studies. In RCTs, only BMI of 30 or higher was negatively associated with treatment response (PASI 90 at 3 months: OR, 0.57; 95% CI, 0.48-0.66). CONCLUSIONS AND RELEVANCE: This meta-analysis found that patients with psoriasis who smoke or have a history of smoking, as well as those with previous exposure to biologics, older age, or higher BMI, exhibited poorer response to biologics in observational studies. However, it remains unclear whether these clinical characteristics influence treatment response differently for the different biologics available for psoriasis.