Abstract: The purpose of the study was to explore the development of spatial transitive inference ability of preschoolers, comparing the children's inference ability in 'front and behind' and 'up and down' tasks, and to investigate their transitive inferences in different experimental situations (consistent, ambiguous, contradictory). So two kinds of spatial positions were used, one was'front and behind', the other was'up and down'. In order to lessen the memory load, the participants were asked to make transitive inference operations according to the premises presented to them. In 'front and behind' tasks, five kinds of models of small animal toys that can stand consisting of tiger, ox, sheep, pig, monkey with three respectively were used. In'up and down' tasks, six kinds of magnetic models of small animal toys consisting of bear, rabbit, cat, pig, dog, and panda with three respectively, and a vertical iron plate were used. There were two steps in each task. First, two-toy premises were presented to the children, then they were given three extra toy models and asked to put them in order. There were two premises in each task: A-B,B-C. If A was in front of (or above) C by sight, that was a consistent situation. If A was the same level as C by sight, that was a ambiguous situation. If A was behind (or below) that was a contradictory situation. A total of 72 children from a kindergarten were examined. There were 24 children in each 4,5,6 year old group (12 boys, 12 girls). The results showed: (1) children as young as 4 years of age developed the ability of spatial transitive inference; (2) the development of cognitive capacity of'up and down' position was faster than that of 'front and behind' position; (3) 4-6 year old children couldn't completely ignore the situational influences in order to form a kind of stable transitive inference ability.

Key words: preschoolers, transitive inference, spatial position