Methods of processing, storage, use and disposal of sewage sludge according to the possibilities of methane formation were defined and conditions for the application of these methods (aerobic-anaerobic) and methane conversion factors (MCF) potentially available for each method (based on expert assessments and by carrying out researches) were evaluated in this work. The work was initiated by fulfilling the requirements of the United Nations Framework Convention on Climate Change (hereinafter - the UNFCCC), the Kyoto Protocol and the EU’s decisions 280/2004/EC and 2005/166/EC according to which the national report on accounting of greenhouse gas emissions must be submitted annually to the Convention Secretariat and the European Commission, and in the part of report on waste, in accordance with Good Practice Guidelines developed by the Intergovernmental Committee on Climate Change (2000), calculations of greenhouse gas emissions (methane) in wastewater and sludge must be provided. Experts of the UNFCCC Secretariat in their Report on the National Report on Accounting of Greenhouse Gas Emissions submitted in 2011 noted that the calculations of storage of methane from sludge were not carried out.