This study is the part of development of a global system of forest carbon monitoring, using satellite remote sensing data, inventory data, and ecosystem model. We study the requirement of the national, regional, and site-level forest inventory and examination of data acquisition, management, and analysis to contribute the system. We have mainly made use of ALOS/PALSAR data to analyze and evaluate the forest inventory data through collaboration with the international partners. It was clarified that there remain problems in analyzing satellite data and inventory data in an integrated manner. The study also accomplished the objectives including the design of forest inventory database for the system. This study has collaborated with GEOSS activities under the new task "CL-09-03: Global Carbon Observation and Analysis System" of "Forest Carbon Tracking" and other international activities to establish the global-scale Forest Carbon Monitoring System.