Through modifying proportions of potassium nitrate, sulfur, phenolophthalein and potassium hydrate, formula of charcoal-free black powder is optimized by replacing charcoal with reactant of phenolphthalein and potassium hydrate. Properties between ordinary black powder and charcoal-free powder are compared, including mechanical sensitivity, static eletricity sensitivity, thermal decomposition process and output capacity.The results indicate that the mechanical sensitivity, static electricity sensibility and ignition temperature of charcoal-free black powder is lower than that of ordinary black powder, and the safety ability, working capacity and output stability of charcoal-free black powder is higher than that of ordinary black powder.