In this paper, a single mode buried polymer waveguide on silicon dioxide layer on silicon substrate is presented. The waveguide was completed by first obtaining the optical field distribution using a beam propagation method. The waveguide structure is carefully designed to ensure a single-mode operation of this device. The waveguide was fabricated by first etching a trench on SiO2 layer. Then Benezocy-clobutene (BCB) polymer was deposited onto the layer and cured in proper conditions. Finally, a thin hybrid sol-gel layer was used as the top cladding layer after the BCB polymer etch-back process. The propagation losses are 0.91dB/cm and 0.97dB/cm for TE and TM polarized lights. The polarization dependent loss is 0.06dB/cm. The coupling loss of the waveguide is 1.78dB.