中文摘要：

基本养老保险投盖面狭窄是西部地区养老保险发展长时间面临的主要矛盾，是目前严重制约养老保险体制改革进程中的首要因素，文章以西部地区基本养老保险为视角，运用西部12个省份的面板数据，探讨西部地区基本养老保险的区域差异和影响因素。分析结果表明：经济发展水平是扩大西部地区基本养老保险覆盖面中一个重要而积极的因素，城市化水平对于基苓养老保险覆盖面的扩大，人均养老金待遇是覆盖面难以扩大的主要原因。基于此，从财政投入、养老金制度等方面提出了相应的政策建议。

英文摘要：

The narrow coverage of basic old-age insurance is the prominent contradiction faced by the long-term develop-ment of old-age insurance in western regions.and it is also the primary factor which constrains seriously the process of re-form of current old-age insurance systems.From the perspective of the basic old-age insurance,and using the panel date of 12 provinces in western regions.The paper explores that the regional differences and influencing factors of the basic old-age insurance in western regions.The results show that the level of economic development is an important and positive factor to expand the basic old-age insurance.The per capita old-age income is the main obstacle to increase the coverage of the ba-sic old-age insurance.Based on the rescarch,the paper puts forward some corresponding policy recommendations from finan-cial support,the basic old-age insurance systems and so on.