Abstract: Abstract: From ‘buffett tax’ to ‘unequal cost’ by Joseph Stiglitz.From ‘Piketty tax’ to 2015 Nobel prize-winning economist Angus deaton,who is award by attention to the problems of the income gap. Income gap is always accompanied by human society development for a long time, which is unable to avoid and has the very strong practical research value.We begin this article with the analysis on the debate of the ‘Capital in the Twenty-First Century’,and discusses the background and feasibility of the Piketty tax. We respectively analyze the status of the income gap and the current situation and difficulties of the social security system according to European countries, America, east Asia and Latin American countries,aimed to explore the realistic origin of Piketty tax. Then we analyze the situation of the income gap and the social security system of China.we give the details supporting measures about Piketty tax: The reform of tax system and distribution system; Draw experiences and lessons from the historical experience of western developed countries;The implementation of inclusive growth of fiscal and taxation reform.Strengthen and improve the system of tax regulation of ‘walking on two legs’ and the social security at the same time.We should pay attention to the restraint of the ‘public welfare impulse’ of government and residents and build a more sustainable system of public financial revenue and expenditure.

摘要： 摘 要：从“巴菲特税”到斯蒂格利茨“不平等的代价”，从“皮凯蒂税”到2015年诺贝尔经济学奖获得者迪顿因对收入差距问题的关注而获奖，收入差距问题是始终伴随人类社会发展长期存在、无法回避的“痼疾”，具有很强的现实研究价值。本文从《21世纪资本论》的争论分析入手，探讨了对高收入者征收“皮凯蒂税”命题提出的背景及征收的可行性。我们分别针对欧洲国家、美国、东亚地区及拉美国家的收入差距状况、社会保障体系的现状与困境进行分析，探讨了征收“皮凯蒂税”的现实根源；接着我们分析了中国收入差距状况及社会保障体系的情况，详细分析了“皮凯蒂税”发挥作用的配套措施：改革税制和分配制度；从西方发达国家的历史经验中汲取经验和教训；实施“包容性增长”的财税改革，在不失时机地对高收入群体加强税收调控以及完善社会保障制度“两条腿”走路的同时，注意克制政府和居民的“公共福利冲动”，构建更加可持续的公共财政收支体系。