Background: Psoriasis is a common immune mediated and chronic inflammatory skin disorder portrayed as hyperproliferation and maturation impairment of keratinocytes, increased immune cells infiltration and blood vessel formation, and accumulation in proinflammatory cytokines. Psoriasis is now considered a systemic disease where it is associated with psychological, metabolic, arthritic, and cardiovascular comorbidities. Lifespan is reduced as a consequence. Objective: The aim of this study was to evaluate serum level of adipocyte fatty acid-binding protein (FABP4) in patients with psoriasis vulgaris and to compare it with its level in healthy control. Patients and methods: Seventy-four were included in this study. They were chosen from the Out-patient Clinic of Dermatology, Andrology & STDs Department, Mansoura University Hospitals. A case study group of 37 patients with psoriasis vulgaris and 37 of healthy people age- and sex-matched were used as a control group. Results: ROC curve for detection of FABP4 before acitretin validity in differentiating studied cases illustrated excellent area under curve of 0.728 (p < 0.001)* with the best detected cut off point was 2.7 yielding sensitivity of 75%, specificity of 81.1% and total accuracy of 78.1%. So, the present study demonstrated that; detection of FABP4 level before acitretin therapy could be used as reliable indicator in differentiating studied cases with high sensitivity and specificity. Conclusions: Serum FABP4 levels were significantly increased in patients with psoriasis, indicating that this protein may be a potential marker of psoriasis and an independent predictor for the risk of comorbidities or complications in psoriatic patients. Additionally, it could be used also as a reliable indicator of acitretin therapy.