No one deny the significance of circular economy and carbon neutral system these days. However, there has been few attempts to pursue these multiple goals at once at a city level. This study aims to question and –partly- answer on this topic in the cases of SMG’s relevant policies. The first part of the study is devoted to analyse the current SMG’s Green House Gas Inventory system. Following analysing the GHG of Waste sector chronologically, factor sensitivity analysis was conducted to figure out the major elements from the Indirect GHG calculated from the Seoul Metropolitan Area Landfill and the Direct GHG drawn from the Waste-to-Energy Facilities, i.e. incinerators, in Seoul. Papers, Other

combustibles of municipal waste are one of top contributors to Landfill-originated GHG emission, whilst Plastics and Other combustibles to incineration-originated GHG emission. The second part of the research is filled with the comparative studies of given GHG reduction units related to the waste sector. First, we calculated the GHG reduction  effects of four projects that SMG recently adopted in 2021 and 2022: the 1st batch of Zero-waste stores supported by SMG, the current support schemes of reusable cups and food containers and the recycling grants programme of coffee grounds. In comparison with the given GHG reduction units by the Korean Environment  Corporation, further more the baseline activities, the calculation results indicated positive effects in GHG reduction via implementing circular policies. In the last chapter of the study, policy recommendations are listed in an order of applicable and desirable time plan.