As "Forest Carbon Offset Scheme" of Korea Forest Service was launched in 2011 and 『Act on Management and Improvement of Carbon Sink 』was enacted in 2012, it is expected that applicability of Forest Carbon Offset Credits will be gradually becoming wider in national climate change response activities. Up to now, Korea Forest Service has allowed only forestation projects as carbon offset projects in Forest Carbon Offset Scheme, however, it is obvious that it will be difficult to secure the sufficient quantity of lands for plantation because Korea already completed the forest greenification on 1987. So it is essential that forest carbon offset projects need to be developed especially in forest management sector using existing forests in order to improve the usefulness of Forest Carbon Offset Credits. Under the practical necessity, this research suggests the methodologies and implementation strategies for forest carbon offset projects in forest management sector through case studies and experts surveys. As the results, this study proposes extension of rotation age, regeneration of tree species, diminution of harvesting volume and thinning as specific project types. This study also proposes the guidances about scenarios for baseline and project, additionality, project period, carbon accounting of harvested wood products, and buffer credits system. In conclusion, the most important way for the reputable scheme is benchmarking international outstanding schemes, however, at the same time, the scheme needs to reflect the domestic real states of relevant legal systems and forestry circumstances for stability of the scheme.