Abstract: The objective of this paper is to explore the relationship between family intimacy and depression and the mechanism of loneliness in the relationship between family intimacy and depression. The methods are as follow:310 college students were measured by family environment scale (FES), depression self-rating scale (CED-S) and loneliness scale (UCLA). We get the following results:(1) college students with poor physical health were more likely to suffer from depression and loneliness, and college students with broken family relationship had lower family intimacy; (2) there was a significant negative correlation between family closeness and depression. There was a significant positive correlation between loneliness and depression. There is a negative correlation between family closeness and loneliness. (3) family intimacy and loneliness have significant predictive effects on depression, and loneliness has some mediating effects between family intimacy and depression. Finally we come to such a conclusion:whether family intimacy directly or indirectly regulates depression through loneliness, it has a significant effect.