The self-concept is composed through the interaction with others (Mead,1934). As selfconceptual study in early childhood, most targets the same age others. However, it is thought that the existence of the others at other stages of development brings the influence to the self-concept if the self-concept is composed by the interaction with others. The present study aimed to search for children's understanding of stages of human development and children's self-concept by the comparisons between others at other stages of development. Then, the card task and the interview were executed. In card task, participants were made to arrange it in order of growth with baby, child, grade-schooler, adult, and old people's five photograph cards. As a result, being able to arrange correctly was 4years old 22%, 5years old 43%, and 6years old 96%. In the interview, it was heard to participants to understand four stages of development other than child. Afterwards, it was asked which was good as them who that were each stages of development and present. As a result, it was shown to come to catch the feature of each stages of development more deeply as the age went up though it was knowledge that relied on the overall, visible side. Moreover, in the comparison with other stages of development with present participants, it has been understood that 4years satisfaction to the self is high, 5years have the individual variation, and 6years hold the yearning to the old people except the older person.