To study the characteristics of close social relationships and its influences on life satisfactions in the middle age, convoy model was used through interview with 315 middle aged men and women. Participants were divided into three age groups(forties, fifties, sixties). In the convoy model distinguishing three levels of closeness, sixties had smallest inner, middle and outer circles and forties and fifties had significant sex differences in the size of convey. Interestingly partner, children, mother and father were included in the inner circle, and sibling, friends, co-workers were included in the middle and outer circle. Outer circle had more various relatives than middle circle. As partner, children and friend were members of inner circle, inner circle was obvious to represent attachment relationships. In addition sixties had more life satisfaction than forties and fifties and sixties with larger convoy than smaller convey.