Abstract: In order to investigate the influence of additives on anti-slagging characteristics of the stalks pellet fuels, three kinds of additives, MgCO3, CaCO3, Al2O3, were added into the pellet fuels to experiment on the slagging characteristics, ash appearance as well as the chemical components of the ash. The results show that adding additives can result in the considerable changes of the ash appearance of the corn stalks pellet fuel, the smaller the size of the ash pellet, the more course and holes its appearance will be. Si, K account for the main elements of slagging during the combustion of corn stalks pellet fuel. The new component of Mg and Ca with Si and K after reaction has anti-slagging effect. The new silicate comes into being after the reaction of Al with Si and K. It is concluded that the new component of additives with Si and K after reaction has anti-slagging effect, and the results can provide a theoretical basis for solving the slagging problems of the stalks solid fuels.