This article begins with the research of LEF'social security situation and questions, analyse reasons, and research old-age insurance, medical insurance, unemployment insurance and lowest social security expense. 本文从研究被征地农民社会保障的现状与问题着手,剖析社会保障缺失的原因,并重点研究了养老保险、医疗保险、失业保险及最低生活保障。