Three granular carbon‐based solid acids were prepared from white poplar and used for the esterification of oleic acid and methanol. The granular carbon‐based catalysts were characterized by elemental analysis (EA), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and specific surface area test (BET) etc. The catalysts demonstrated high activities for the esterification of oleic acid with the conversion up to 98%. The prepared catalysts can be easily recovered and reused in the application process. The effects of carbonization temperature and reaction conditions on the catalytic activities were investigated. The results showed that the catalyst prepared by method‐2 owned excellent stability with the recycled esterification conversion of 90% after five runs.