In order to achieve national greenhouse gas reduction targets, green remodeling is essential to improve the energy performance of existing buildings that occupy a high proportion of building stock. The government has introduced and operated the Green Remodeling assessment criteria in the G-SEED Certification Scheme. The propose of this study is to suggest improvement strategies of Green Remodeling assessment criteria based on the analysis of G-SEED and other international certification schemes related to the assessment of green remodeling. The state-of-the-art of the assessment systems including building types, assessment categories and issues were investigated and compared. Based on the comparative analysis, the implications to improve the current Green Remodeling assessment criteria were suggested. The results of this study can be used as the basic data for the revision of Green Remodeling certification assessment criteria of G-SEED in the future.