types of absorber，atmosphere， ratio of calcium to chlorine，and fuel mixture ratio on the dechlorination of wood chips and PVC during cofiring under O2 /CO2 atmosphere were investigated by using a tube furnace． The results show that with the increment of the temperature， the dechlorination efficiency increases firstly and decreases subsequently． Meanwhile， the highest dechlorination efficiency is 71. 4% at 700℃． The ratio of additives has a certain impact on dechlorination． Modified calcium carbonate can increase the dechlorination rate at a high temperature，because the pore structure becomes more abundant and the specific surface area becomes relatively larger． As the mixing ratio of sawdust rises，the dechlorination efficiency increases， and the dechlorination efficiency in O2 /CO2 atmosphere is higher than that in O2 /N2 atmosphere． The analysis of BET and SEM/EDS on sorbent and product indicates that the surface of the product particle covers the layer of dense CaCl2，which prevents the HCl from penetrating the particle surface into the dechlorination agent inside the full reaction． The reaction becomes inadequate，which leads to the reduction in dechlorination efficiency．