Psoriasis is a chronic and inflammatory dermatologic disease. Psoriasis may predispose to cardiovascular disease and diabetes. However, the role of tumor necrosis factor (TNF) inhibitor in mediating this risk is controversial. Regarding frequent use of infliximab in psoriasis, and the hypothesis that anti TNF-α treatment may increase Body Mass Index (BMI) and alter lipid profile in these patients, the aim of this study was to assess changes in BMI and Lipid Profile and level of leptin in Psoriatic Patients under Treatment of Standard Protocol of Infliximab in a 24 week period. This study was accomplished as a before-after study. Twenty-seven psoriatic patients were included, and standard infliximab therapy was applied. All patients underwent 3 times of blood collection and in each session; LDL, HDL, Total Cholesterol, Triglycerides, Leptin, and PASI score were measured at the start of the study and at the 12th and 24th week of follow-up. Twenty-five patients consisted of 18 (72%) male and 7 (28%) female subjects were evaluated. The mean age of the patients was 36.91±13.31 years. PASI score demonstrated significant decrease after 24 weeks; however, BMI and HDL and leptin showed a significant increase during treatment. Significant negative correlation was seen between Leptin and PASI score changes (r=0.331, P=0.042). HDL and BMI had the most correlations with leptin (positive correlation) and PASI score (negative correlation). Results demonstrated a dramatic decrease in PASI, increase in BMI and HDL and increased in leptin; somewhat correlated to each other. These results suggest that patients taking infliximab should take more care of their weight and lipid profile, while on treatment.