Purpose: This study was based on J. W. Atkinson's theory of achievement motivation. The purpose was to investigate the effect of tremendous discrepancy between parents' expectations and children's actual intelligence on children's tendency to achieve success and to avoid failure. 　　Procedure: The subjects were 681 8th graders randomly selected from public junior schools in Taipei City. All the subjects were given both Intelligence Test and Questionaire of Parents' Expectations. Then translate their scores on these two tests into standard scores respectively. The children whose parents' expectation levels were higher than one standard deviation of the children's intelligence score were considered to be the high expectation group and those whose levels were lower than one standard deviation of intelligence score were the low expectation group. All the children whose parents' expectation levels and the children's intelligence score were of a standard score of ± .20 were considered to be moderate expectation group. The subjects were divided into three groups as mentioned above, each consisting of 80 persons (45 boys and 35 girls) with intelligence score from 80 to 120. 　　Findings: The main findings of the study were: 1. Boys in the moderate expectation group had a stronger tendency to achieve success than the high expectation group and the low expectation group. 2. Boys in the high expectation group had a stronger tendency to achieve success than the low expectation group. 3. Girls in the moderate expectation group had a stronger tendency to achieve success than the low expectation group. 4. Boys in the high expectation group had a stronger tendency to avoid failure than the low expectation group. 　　Conclusions: Based on the evidences given herein, the following conclusions were drawn: tremendous discrepancy between parents' expectations and children's intelligence had bad effect on children's tendency to achieve success, especially on boys. 　　Recommendations: According to the above findings and conclusions, some suggestions were made: 1. Parents should understand their children's ability better. 2. Parents should set up an expectation level that can be reached by their children. 3. Parents should have a proper attitude toward educating their children.