Adequate and stable investments are indispensable pre-conditions for China to mitigate and adapt to climate change and achieve its Nationally Determined Contribution (NDC).Based on the system optimization model PECE,coupled with the adaptation module,the study expanded and constructed a comprehensive bottom-up analytical framework and assessed the mitigation and adaptation financial needs in implementing China's Nationally Determined Contribution.Both mitigation areas such as low-carbon energy,energy saving,forest carbon sink and adaptation areas such as infrastructure,agriculture,water resources,coastal zones and related sea areas,forests and other ecosystems,and human health have been covered.The study further identified the potential finance gaps by comparison with current financial inputs and put forward corresponding policy recommendations.Based on the analysis,the study finds out that between 2016 - 2030,China's total finance needs to achieve its NDC targets will reach 56 trillion yuan,an average of 3.7 trillion yuan per year,of which financial needs for mitigation and adaptation will reach an average of 2.1 trillion yuan and 1.6 trillion yuan respectively.With the enhancement in mitigation efforts and the increase in climate change risks,the average annual finance needs will increase accordingly,and will increase from the annual average of 2.9 trillion in the 13th Five Year Plan to 3.8 trillion Five Year Plan in the 14th Five Year Plan,and to 4.5 trillion yuan for the 15th Five Year Plan.Compared with the existing scale of financial investment,it will face a finance gap of 1.4 trillion yuan each year.It is very necessary and urgent to increase and stimulate the investment in climate change,not only to expand the scale of climate investment,but also to further adjust the investment mode and structure of climate finance,with more attention on areas as non-hydropower renewable energy,energy saving in building and transportation sector,smart grids and energy storage,sustainable infrastructure,and disaster prevention and mitigation.