Secukinumab demonstrated high efficacy and favorable safety profile in patients with moderate‐to‐severe plaque psoriasis (PsO) in clinical trials. However, understanding of patient characteristics and clinical outcomes in real world in Thailand is still limited. To describe patient characteristics, effectiveness and safety of secukinumab in Thai PsO patients. This retrospective study analyzed data from medical records of adult PsO patients who initiated secukinumab at 7 dermatology centers from September 2017 to April 2021. Study outcomes included patient characteristics and changes in Psoriasis Area and Severity Index (PASI) score from baseline at weeks 4 and 16 after secukinumab initiation. Adverse events were recorded. Subgroup analyses by adherence rate and completeness of loading dose were performed. Of 163 patients, the mean (SD) age was 44.0 (14.0) years. Most patients (84.7%) were previously treated with topical therapy while 62.0% and 21.5% of patients had received systemic and biologic therapy, respectively. The mean baseline PASI score was 15.4 (9.3). Overall, the mean PASI score improved by 58.0% at week 4 and 78.4% at week 16. Statistically significant differences in PASI approvement were revealed among subgroups of patients with different loading dose and adherence rate. Adverse effects were reported in 8.0% of patients. The characteristics of patients in this study were slightly different from clinical trials in terms of demographic and clinical characteristics, as well as PsO treatment. Secukinumab was effective and safe in Thai patients with PsO, especially among those with complete loading dose and a higher adherence rate.