On the basis of the molecular structural character in the composition of propellants and explosives and the change of elemental oxidizing state in burning or explosive. Three chemical cri- teria:the number of oxidizing states. absolute exidizing states and actual absolute oxidizing states are suggested.With the aid of these chemical criteria
not only the oxidizability and combustibility can be interprcted
but also its potential and actual reaction feature can be expressed. It is very im- portant to understanding the molecular feature of propellants and explosives.