Abstract: The rural area is experiencing a rapid change in economic and social development,so it is necessary to study the households' life quality and its influencing factors during the transformation. As a subjective evaluation to the overall standard of living and all kinds of objective living conditions,life satisfaction has become one of the key indicators to measure the subjective life quality. Recently,the social capital theory has gradually become an important method to analyze the subjective life quality in the field of human economic and social sustainable development,and a new perspective to explain the differences of the individual's life satisfaction. In this paper, based on the external social capital,including five dimensions,community participation,social networks,social interaction,trust,common willing,the Hongjia town in Changwu County,Shaanxi Province,China is selected as a case study for exploring the differences of the households' social capital characteristics and their life satisfaction, and the effects of the social capital on the households' life satisfaction is discussed particularly. The findings are as follows:Firstly,the overall life satisfaction is low,and life satisfaction of the pure households,multiple occupations households and non-agricultural households ranks in a descending order. Secondly,there are significant differences in the social capital among the four types of local households,which shows that the social capital of the households with various means of livelihood is higher than that the ones with single mean of livelihood. Besides,the improving of the rural households' social capital contributes a positive effect on their life satisfaction. Social network,interaction,trusts and common willing are important social factors to affect the life satisfaction of the rural households. And the key factors affecting different types of rural household' life satisfaction are different,which are respectively expressed as follows:Social interaction corresponding to agricultural households, social network corresponding to the household with agricultural and other means of livelihood,trust corresponding to the households with other dominant means of livelihood and non-agricultural households. Finally, this paper points out the shortcomings of the research,puts forward specific suggestions in order to improve the households' quality of life in the western rural area effectively,and provides the theoretical support and reference for targeted poverty alleviation.

Key words: rural household, social capital, life satisfaction, multi-variant ordered logistic regression, Loess Plateau