The aim of this study is to investigate the demographic and clinical characteristics of patients receiving biological therapy for psoriasis. All patients who received biological treatment for psoriasis were included in the study. Characteristics of patients and PASI responses' rates were evaluated at 6, 12, 16, 24, 36, and 52 weeks. One hundred and three patients enrolled. Of all, 28 patients were using adalimumab (27.2%), 26 were using secukinumab (25.2%), 22 were using infliximab (21.4%), 22 were using ustekinumab (21.4%), 5 were using ixekizumab (4.9%). PASI75 response rates at sixth and 52nd weeks; were 68.1% and 95% for infliximab, 64.3% and 100% for adalimumab, 77.3% and 100% for ustekinumab, 76.9% and 81.3% for secukinumab, respectively. The most common reason for biologic switching was secondary failure. Treatment failure was the main reason of switching therapies. In our study, no statistically significant difference was found between efficacies of biological drugs. It remains unclear in what order and how exactly biological agent switching should be done. There is a need for large-scale studies on the treatment response rates, and survival times of different biologics.