Abstract: While China's economy is growing rapidly, the income gap is also widening. This paper relies on Roemers “environmentefforts” binary analysis theory, adopts exante parameter method, uses China Laborforce Dynamics Survey Data (CLDS) to measure the changing trend of China's inequality of opportunity in recent years, decomposes the inequality of opportunity, analyzes the impact of household registration, family, gender and other factors on inequality of opportunity, and discusses the effect of city size, city location difference and administrative level difference. The results show that the inequality of opportunity in China is on the rise, and there are obvious regional differences from the eastern coastal areas to the western inland areas. There are different characteristics in urban and rural areas, in different genders and ages, and there is an inverted Ushaped relationship between inequality of opportunity and urban size. High level cities such as municipalities and provincial capitals tend to have a lower level of opportunity inequality.

Key words:  , inequality of opportunity, city size, family background, urbanrural differences, shapley decomposition

摘要： 中国经济快速增长的同时，收入差距也在不断扩大。本文依托Roemer的“环境—努力”二元分析理论，采用事前参数法，利用中国劳动力动态调查数据（CLDS）测度近年来我国机会不平等的变化趋势；对机会不平等进行了分解，分析了户籍、家庭、性别等因素对机会不平等的影响程度，探讨城市规模、城市的区位差异和行政等级差异对机会不平等的影响。研究表明，中国的机会不平等程度呈上升趋势，从东部沿海到西部内陆存在明显上升的地区差异，在城乡、性别和年龄等方面都呈现出不同的特征；且与城市规模之间呈倒U型关系，直辖市、省会等高等级城市倾向于有更低的机会不平等水平。

关键词: 机会不平等, 城市规模, 家庭背景, 城乡差异, Shapley分解