Plastics are classified according to their source (petrochemical, bio) and degradability (recalcitrant, biodegradable), with short-lived petrochemical-based plastics (67% of global plastic waste) being the most problematic (mostly classified as municipal waste). While the consumption of plastics is growing rapidly, the actual recycling of the material is currently only 30% of the 69.2% (2020) of input-based recycling. The rest is made into solid fuels, recycled for energy recovery, or disposed of as recycling residues. Through the Ministry of Environment's full-cycle post-plastic measures and the 2030 Zero Plastic Plan being prepared by the Seoul Metropolitan Government, eco-design manufacturing that increases reduction and circularity from the production stage, the introduction of a mandatory percentage system for the use of renewable raw materials, and the introduction of chemical recycling as a new recycling method have been discussed in earnest, but there have been no studies on how to innovate on existing local government tasks such as post-plastic separation and collection. Seoul's recycling rate has also been stagnating or declining for the past five years, suggesting that it is time to shift existing policies that focus on increasing recycling inputs. It is necessary to conduct technical and policy analyses and explore alternatives on how to innovate the separate waste collection system for recyclable materials in charge of autonomous districts and Seoul Metropolitan Government to reflect recent technological and institutional changes. In the last chapter of the study, policy recommendations are listed in an order of applicable and desirable time plan. In response to diversified recycling methods, a change in the collection system is needed. Securing recycling space for citizens and improving the efficiency of sorting centres, as well as piloting special bags and promoting chemical recycling simultaneously.