Pyrolysis, as a thermo-chemical conversion process, has a large environmental friendly potential feature driven by an increased interest in renewable energy sector. Literatures suggest that the process can successfully be applied for converting green waste into bio-energy. Pyrolysis oil, gas and charcoal contain significant thermodynamic properties for heat and power generation for various types of industries. Municipal Green Waste is considered as one of the significant sources of feedstock to produce energy from a renewable source. Energy recovery from green wastes has several positive environmental implications, resulting in less or no net releases of carbon dioxide, very low sulphur content, and reduction of greenhouse gas (GHG) emissions, mitigation of acid rain by reducing SO2 and NOx and soil amendments. Much research is needed for identifying effective and efficient ways of green waste management and its potential for commercial applications for bio-energy production. This paper reviews and summaries the environmental impacts of green wastes to energy conversion through pyrolysis process.