To investigate the reliability of the Achievement Motivation in Physical Education Test (AMPET) and reexamine its factor structure, 10,055 elementary, junior high, and high school students in Japan were tested. The AMPET has seven 8-item subscales consisting of learning strategy (LS), overcoming obstacles (OO), diligence and seriousness (DS), competence of motor ability (CMA), value of learning (VL), anxiety about stress-causing situations (ASCS), and failure anxiety (FA), respectively. The ASCS and FA subscales are associated with negative aspects of the AMPET, while the other five sub-scales are related to positive aspects. The AMPET also contains an 8-item lie scale. The subjects were asked to respond along 5-point Likert rating scales. Item-subscale correlations of the AMPET were sufficiently high. Alpha reliabilities ranged from .797 to .950, and test-retest reliabilities after 5 weeks were .651 to .883. Elementary school pupils showed significantly higher mean scores on the positive aspects of the AMPET than junior high and high school students. The means of female students on the negative aspects of the AMPET were significantly higher than those of male students. Seven factors were extracted from the principal components factor analysis with normal vari-max rotation. Each factor was composed of the seven different subscales of the AMPET.