Abstract: Many scaling procedures have been developed in the recent ten Years. But none of them has been recognized as the general rule for :the scaling of combustion systems of turbojet engines and gas turbines. The present paper deals with the general method for finding the possible scaling rules of such systems. After presenting the scaling theory with respect to the liquid droplet spray combustion systems, The author examines the existing works in that field on the basis of the suggested theory. New scaling procedures are proposed and some conclusions are drawn.