In the present study, the peat, as solid waste, was utilized as the support to prepare carbon solid base catalyst for biodiesel production from palm oil. The chemical and structural properties of catalysts were examined by thermogravimetric analysis (TGA), scanning electron microscope (SEM), energy dispersive spectrometer (EDS), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), N-2 adsorptionfdesorption and the Hammett indicator method. The results indicated that 30K/PB-600 catalyst exhibited the highest catalytic activity (the maximum biodiesel yield of 98.6% was acquired) owing to its highest total basicity. Besides, the stability of the catalyst during reaction was also demonstrated. After 9 repeated use, the catalyst could still possess a rather high catalytic activity (biodiesel yield of 81%). The little deactivation of catalyst was mainly owing to K+ ions leached into reaction media. Therefore, biochar derived from peat could prove to be an appropriate material for catalyst synthesis. (C) 2017 Elsevier Ltd. All rights reserved.