Four traditional eliminated-flame additives(LiF,KA,C₄O₆H₄K₂ and KD) were adopted in grain cast propellant,and its effects on the combustion performance and characteristic signal of the propellant were studied. The motor experiment results show that KA and KD suppress after burning. More than 80% flame area were reduced. Burning rate of propellant is increased with the eliminated-flame additives. Results show IR and visible light permeation rate of grain cast propellant is slightly reduced,and laser permeation rate is increased.