Experiments were conducted to examine the role of moisture in activated charcoal on the performance parameter like burn rate and burn rate pressure index of the aluminized composite solid propellant. Propellants with moisture present in the activated charcoal were cured and shown to be free from blow holes and voids. They were also shown to have good mechanical properties. It was noticed that burn rate and burn rate pressure index is higher for propellant composition containing very small percentage (0.16 % and 0.6 % of the weight of the propellant) of moisture trapped inside the pores of activated charcoal as compared to the composition without moisture. Propellants were also prepared to examine the role of moisture in activated charcoal when mixed along with other known burn rate modifiers like copper chromite and iron oxide. Activated charcoal with moisture along with known burn rate modifiers like copper chromite or iron oxide futher increased the burn rate as compared to the propellant containing only copper chromite or iron oxide. © 2011 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.