Glycidyl azide polymer (GAP) has been prepared and studied for its application as polymeric matrix for composite solid rocket propellants (CSRP). Different CSRP based on GAP polymeric matrix with different plasticizers were prepared. A cross-linker based on trimethylol propane (TMP) and dibutyltin dilaurate (DBTDL) was added to the GAP matrix to ensure curing completion of the prepared CSRP. The viscosity and shore A of all the prepared CSRPs during the curing process were measured continuously. The mechanical properties of the cured CSRP were determined. The ballistic performance, burning rate at operating pressure and specific impulse were determined using standard a modified six inch rocket motor with 16.25 mm nozzle. By comparing the results, it was concluded that the plasticizer; dioctyl azelate and dibutyl phthalate are not compatible with GAP matrix. In addition, CSRP based on GAP has specific impulse and burning rate slightly higher than the traditional HTPB based CSRP.