This study was carried out to develop for the emission factor of greenhouse gas (GHG) from medium and smallscaled incineration facility using RPF which is considering as a part of renewable energy in UNFCC. The actual concentration of the exhaust gas and the fuel composition of RPF were measured for the calculation of GHG emission factor in RPF incinerators, and were compared with the IPCC guideline. The $CO_2$ and $N_2O$ emission factors by the actual concentration of exhaust gas were $2.3575{pm}1.0070tCO_2/tRPF$ and $0.0014{pm}0.0014tN_2O/tRPF$ respectively. Also, $CO_2$ emission factor by the RPF composition was $2.7057{pm}0.0540tCO_2/tRPF$. The GHG emission factor per energy by the actual concentration was $83.0867{pm}26.0346tCO_2e/TJ$ which showed higher consistency with the GHG emission factor ($80.3967tCO_2e/TJ$) of waste plastic in the IPCC guideline (2006b). The $CO_2$ and $N_2O$ emission factor calculated in this study is considered as a meaningful data for GHG emission factor of RPF incineration facility because of not being developed in ROK.