The CDM afforestation and reforestation project is one of the key approaches for coping with climate change. The accurate data of carbon storage of this project depend on the reliable monitoring method. Understanding the methods of carbon storage estimation will aid the development for the CDM afforestation and reforestation worldwide. This paper elaborates the monitoring techniques, index and calculate method for the carbon storage estimations for the first CDM reforestation project that developed in China. The results indicated that the net anthropogenic GHG removals by sinks (namely carbon storage change) was 131 964.1 t CO_2, and the measurement accuracy was 90.15%, since implementation of the project for 6 years. Our results showed that the monitoring method of carbon storage used in this project was suitable and its results were also reliable.