Based on the posible phenomenon of self-fulfiling prophecy in the classroom instruction, it is reasonable to assume that the parental expectations would affect students' school achievement. This study examined the relationships between high school students' academic achievement and the discrepancies between their perceptions to parental expectations and the perceptions of their own school performance. 1511 twelfth grade students were drawn from 15 classes in which the top five students were selected as high achievers and the bottom five students were selected as low achievers. A questionaire of 30 statements concerning school work was administered to the students. The subjects were asked first to respond to each statement in terms of the perceptions to parental expectations, and second to respond in terms of the perceptions of their own performance. The main findings were: (1) The discrepancies between perceptions to their parents and their own were smaller in high achievement group than that in low achievement group. (2) Significant differences were found in the sample on 8 of 30 statements between the discrepancies obtained from the two groups. The educational implications for parental expections were discussed.