Molecular mechanisms of the impact of ultraviolet (UV) rays on biological systems can be divided into three categories: structural and functional changes of DNA, photoinactivation of proteins and structural damage of cell membranes. Though a large number of studies have explored the first two categories of UV ray impacts on biological systems and have proposed various feasible models for the pathways of these impacts, few studies have explored structural damage of cell membranes and the only proposed mechanisms for this UV impact is that of lipid, peroxide, and amino acid oxidation with the impact of various wave lengths of UV rays, A (400-320 nm), B (300-275 nm), and C (275-180 nm) being explained by these mechanisms. In the present work, we have studied the biological impact of UV rays on the phospholipid bilayer by using simultaneous small and large angle X-ray diffraction method.