Accumulation of plastic wastes in the marine eco-system is growing rapidly with the increase of plastic production and consumption patterns, particularly single-use plastics as well as unsustainable plastic waste management practices. Land-based sources are recognised as the main cause (up to 80% of total marine debris) of marine plastic pollution. Marine plastic pollution has thus become an issue of global focus and many national and local governments are searching for solutions to tackle it. Rapidly developing economies, including countries in Southeast and South Asia are contributors to marine plastic pollution due to the lack of plastic waste management policies, governance systems, resources, capacities and infrastructure to keep pace with urban growth and economic development in the respective countries. Many local governments lack sufficient plastic waste collection and environmentally sound treatment and disposal methods. Plastic waste recovery and recycling systems are also not well established and plastic recycling businesses are commonly operated by informal or small and medium enterprises (SMEs). Due to the lack of sustainable plastic waste management systems, littering, open burning and unmanaged disposal of plastic waste are common practices in low and middle-income countries and such practices have largely contributed to costs related to environmental pollution, public health and economy. Both regions have also being used as a dumping ground for plastic waste from other developed countries after China stopped in importing waste from foreign countries since 2017. Based on the literature review and action research in two selected Asian countries, Indonesia (Southeast Asia) and India (South Asia), this report identifies the urgency of addressing plastic waste within the overall waste management policies and systems of the respective countries or cities to reduce marine plastic pollution. It also proposes a list of strategies and policy interventions to consider in reducing plastic pollution from land-based pathways. These strategies are discussed along the plastic value chain in a holistic manner and presented under key policy interventions, such as regulatory, economic, technology, data/information and voluntary measures, identified for the short, medium and long-term.