Sulfones have been synthesized in our laboratory for identification and modeling of several thiophenic compounds founds in petroleum derivatives.Dibenzothiophene 5,5-dioxide was obtained by the reaction between the dibenzothiophene and hydrogen peroxide according to the methodology described by Drushel and Miller [1].The product was recrystallized in ethanol and obtained as colorless crystals.The purpose of this work is to report the structure of this compound by X-ray powder diffractometry.The powder diffraction data were collected at 293(1) K on a Rigaku D/MAX diffractometer.From the corrected peak positions, DICVOL91 and TREOR97 suggested a monoclinic unit cell.This result was subsequently least-squares refined using NBSAIDS*83 with FOM´s M20 = 37.0 and F30 = 36.4.The space group (C2/c, No.15) was derived from systematic absences and checked with the program Chekcell.The structure was refined with the Rietveld program FULLPROF99.The atomic parameters of dibenzothiophene sulfone known from multiple film Weissenberg photographs were used in the initial model [2].Final refinement of the data yielded a = 10.106(3),b = 13.815(4),c = 7.129(2) Å and β = 91.639(7)º,RF = 12.62 and RB = 7.17.The molecular structural parameters obtained were correlated with those found by means of ab initio methods applying Functional Density Theory at B3LYP level using basic set 6-31G(d,p).