In this paper, forest protection, short- and long-rotation plantations, forest regeneration, agroforestry and other activities for carbon (C) sequestration were evaluated. China may be divided into five sub-regions, of which three fall in the main forested areas of China, i.e., the northeast, the southeast and the southwest regions. The forestry mitigation potential in these three regions is the subject of this paper. The Comprehensive Mitigation Assessment Process (COMAP) model is used to calculate the potential for carbon mitigation and the cost-effectiveness of each mitigation option, assuming that 60 percent of the goals of long-term forestry plans of the Chinese government could be realized. The results show that the total sequestered C by the mitigation scenario between 2000 and 2030 for the three regions of China will be 2093 × 106 Mg C, of which 281 × 106 Mg C will occur between 2008 and 2012. The total net biomass sequestration (difference of mitigation and baseline scenarios) from 2000 to 2030 and from 2008 to 2012 is 496 × 106 Mg C and 59 × 106 Mg C respectively. The C sequestration potential could be higher if other two regions are included since the forest area of the two regions amount to 26.5% of total forested area, in particular, the land area suitable for forestation in the northwest accounts for 45% of the total. The activity with least investment cost per unit of C is forest regeneration, followed by long-rotation plantation and forest conservation. The most investment-intensive activity is bioenergy. The total investment for all the mitigation activities is US $12.7 billion. The above figures between 2008-2012 provide an upper bound on the potential for early start projects that might be eligible for the Clean Development Mechanism (CDM). The authors would like to note that the mitigation potential and cost-effectiveness of agroforestry and bioenergy projects need to be further studied.