Psoriasis is a skin disease. It is rare growing disease around the world. Here in this investigation we have targeted a protein namely TRPV3 (Transient receptor potential cation channel, subfamily III) ion channel for the study of psoriasis, which is important factor of psoriasis. The medicinal plant namely Cassia fistula is selected for the in silico investigation. 39 phyto compounds as reported in various research papers are taken for study. Out of 39 phytochemicals, Chrysophanol compound showed highest binding affinity of -7.58kcal/mol having 3 conventional Hydrogen bonds with TRPV3 protein and is found to be a better natural compound as compared to other reported drugs generally used to for the psoriasis. This investigation will lead to more and better findings leading to drug discovery & use as functional food.