The purpose of this study is to find out significant difference between socio-demographical background and family functions which a child perceives. These findings would be a key figures of the child\'s quality of life. First, in order to find out the reliability of the composed criterions, there were factorial and reliability analysis. Second, with a view to investigating socio-demography frequency analysis method is used to get the results of frequency, percentage, average and standard deviation. Third, initiated by t-Test, ANOVA and regression analysis, this study found out the difference of the family functions which a child conceives as socio-demographical transition, and used Duncan\'s Multiple Range Test for the later verification. The results were as follows: As a child, himself, subjectively thinks positive, in other words, as he or she perceives that he or she is healthy, having good scholastic performance, having opulent economic conditions, shows high family competence. In addition, as one has large, diversified family members, likely to shows more emotional intimacy and social cohesion. Therefore child\'s positive thinking and various emotional relations in between family eventually enhance the family functions. In family functions, the median result is that as score of the coherence is high, as considering age of elementary schoolchild, child perceives more sensitive to emotional-intimacy, support and coherence. It needless to say the importance of the family that these emotional side can be fulfilled only by family relationship.