Abstract: This paper answers several academically arguable concepts on implementation and impact of Land Conversion from Farmland back to Forestland in terms of ten years practical experiences in China. A theoretical framework is constructed to explain the policy development of Land Conversion from Farmland back to Forestland. Then it is tested by ten years monitoring data in 100 sample counties in China. Results show that Land Conversion from Farmland back to Forestland was originated from the demand of improving ecology under the economic growth. The goal of fulfilling Land Conversion from Farmland back to Forestland finally relies on economic growth to solve the poverty in rural areas. The implementing problems such as farmers income decline and crop reduction will be resolved with policy adjustment and economic development. Effect of poverty alleviation is obvious because huge amount of subsidies has been successfully delivered to farmers under powerful administration supervision and institutional innovation. Land Conversion from Farmland back to Forestland only achieves the subprime ecological goals in case of generous policy due to incentive incompatibility between farmers private benefit and public benefit. But the sustainability of Land Conversion from Farmland back to Forestland improves because farmers private benefit is combined with public ecological benefit by the project. Strengthening outcomes of ecological construction faces uncertainties due to climate change. Suggestions for future research in policy of Land Conversion from Farmland back to Forestland are proposed.