Agricultural residues are an important and inexpensive bioresource for energy production. In this study the slow pyrolysis technique has been applied to the straw and stalk of rapeseed plant, and the effects of temperature and heating rate on the yields and characteristics of the solid products (biochars) have been investigated. Experiments were performed in a tubular reactor under nitrogen atmosphere at constant heating rate (5 degrees C min(-1)) and varying temperatures (400-900 degrees C) and at constant temperature (800 degrees C) and varying heating rates (5, 10, 15, degrees C min(-1)). The biochars obtained are carbon rich, reactive, and relatively pollution-free potential solid biofuels.