RDF pyrolysis behavior over a temperature range of 773 to 1173K is experimentally investigated by measuring released gas composition and accumulative gas volume in it pyrolysis process for three kinds of RDF, The major combustible components in the released gas were CO, H-2, CH4, C2H6, C2H4, C3H8 and C3H6. A rise in pyrolysis temperature resulted in improved content of combustible gas components, particularly H-2 and CH4. The total heating value of the released gas is dependent upon the temperature and the type of RDF, and higher temperature improves the recycle energy efficiency converted into inflammable gas from RDF, but reduces the volumetric heating value of the gas. The amount of total gas yields can be expressed by a function of temperature and volatile matter content in raw materials regardless of the type of RDF.