In this paper we perform quantum chemical calculation on 2-(3-BROMO PHENYL)1,3-DITHIAN molecule. We deigned this molecule by using X-ray diffraction method and geometry optimized by combination of DFT/B3LYP method and 6-311G(d,p) method with out any symmetry constrain. Normal mode analysis were done by animated gauss view. Calculated frequency were scaled by a scaling factor to compare with experimental one. Electronic properties of given molecule also predicated by using HOMO,LUMO, orbital and MESP surfaces. Our finding are experimental and calculated geometry are well matched with each other. Electronic parameter shows that benzene ring acts as most nucleophile charge center.