Abstract : Psoriasis is a genetically determined inflammatory and proliferative disease of the skin characterized by hyper-proliferation, abnormal differentiation, and inflammatory infiltration in the epidermis and dermis. This chronic papulo-squamous disorder has affected 1-2% of the world population in all geographic areas. It has several morphological variants and identifying the subtype based on histopathology is of utmost importance for better patient care. In various clinical set-ups, immunohistochemistry has evolved over the years and is often used to confirm the diagnosis. The purpose of this study was to analyze various histopathological features of psoriatic biopsies, correlate these features with the clinical findings and study the expression of a proliferative marker Ki-67 using immunohistochemically methods. The prospective study included 50 clinically diagnosed cases of psoriasis and 10 controls with normal breast skin for the duration of two years (2018-2020). Routine histopathology and immunohistochemistry using Ki-67 marker were performed and results obtained from the final data were analyzed in the form of percentages and tables. The typical histopathological features of psoriasis were observed in most of the cases and they correlated with the clinical presentation. Majority of the cases showed mild Ki-67 expression and the mean Ki-67 values decreased as the disease progressed. Also the mean Ki-67 of all the psoriatic patients was higher in comparison to the mean in controls and this difference was statistically significant. Ki-67 is a good diagnostic and prognostic marker showing higher expression in psoriatic disease and can be used for a definitive diagnosis of psoriasis.