Oxidation of strained-Si/relaxed-SiGe heterostructure grown by UHVCVD method using a rapid thermal processing technique in N2O ambient is investigated. The electrical properties of the grown oxide have been characterized using a MOS structure. Hole confinement in the SiGe layer at low field is observed from the capacitance-voltage curve and this suggests that the strain in the initially strained Si epilayer is retained after oxidation. The experimental results are compared with simulation results obtained from a I D Poisson solver. D-it and Q(f)/q values are estimated to be 3 x 10(11) cm(-2) eV(-1) and -1.2 x 10(11) cm(-2), respectively. These high values of D-it and negative Q(f)/q could possibly be due to Ge out diffusion and pile up at the SiO2/strained-Si interface. The oxide exhibits an excellent breakdown field of 15 MV cm(-1).