Abstract: The present experiment was conducted to examine additional variables which might interfere with children's understanding of age. The samples totalled 80 children consisting of 4 groups aged 4 to 7 with 20 children in each group selected at random from kindergartens and elementary schools in Beijing,China.The subject was asked to manipulate the photographs of full-length pictures. Moreover the stature of the figure in the pictures was inversely proportional to his or her age,that is,the taller the younger. Secondly,the objective question referred to the subjects themselves. The results indicated that the understanding of human age went through a process in which time-sequences and time durations related to age were differentiated and integrated progressively.Four and five olds have already had some knowledge about age such as they could tell the differences of age in the light of faces and other clues of the appearance, they begin to know who is older or younger which depended on the birth-sequences and so on, however, their understanding of age is apt to be interfered by irrelevant factors such as the statures of the figure and the rate of growing up. They also hardly understood relative age-sequences.Their cognition of age was also constrained by the developmental level of cognition of number. They did not conceptualize age until they came to elementary school having formal schooling.

Key words: Children, age, cognition