Abstract: Ordered mesoporous carbons (OMCs) with adjustable pores were synthesized by using an ordered mesoporous silica, SBA-15 as a hard template and boric acid as a pore expanding agent. The prepared samples were characterized by X-ray diffraction, N₂ porosimetry, thermogravimetry, transmission and scanning electron microscopy, and Raman spectroscopy. Results show that the pore size of the prepared samples can be finely tuned in the range of 3-7nm by using boric acid as the pore expanding agent. The OMCs possess extensive graphitic domains as evidenced by the well-resolved powder X-ray diffraction peaks, Raman spectra, transmission electron microscope images and thermogravimetric curves. This approach gives a simple method that can be widely used in the controlled synthesis of mesoporous carbons.