Double perovskites Sr2BUO6 where B'=Mn, Fe, Co, Ni,Zn have been prepared as a polycrystalline poder by solid- state reaction. andstudied by X-ray diffraction and magnetic measurements. At 300K, they presentthe same monoclinic distorted crystal structure, space group P21 /n. The perovskite latticeconsists of a completely ordered array of BO6 and UO6 octahedra exhibiting a slight tilting of thetype a-b+a-. Magnetic measurementsshow antiferromagnetism for the phases with B=Co, Ni and Mn at low temperature.The effective magnetic moment at T > TNeel (5.22/ B/f.u. for Co phase and 3.26 B/f.u.for Ni phase) suggests an unquenched orbital contribution. The value for the Mnphase (5.74 B/f.u.) is consistent with that expected for high-spin Mn2+ (5.91 B/f.u.). Thetopotactic reduction of the stoichiometric sample leads to oxygen defficientdisordered perovskites, SrB0.5U0.5O3-d having an orthorhombicdistorted structure, space group Pbnm, at 300K. We will also comment on thetemperature dependent infrared reffectivity of Sr2CoUO6 and isomorphous compounds.