In order to gain an insight into the current situation of middle school students’ physical exercise evading behavior, the authors established and tested a theoretical model of middle school students’ physical exercise evading behavior, selected 480 middle school students as their research subjects, analyzed the current situation of middle school students’ physical exercise evading behavior, and studied the relationships between autonomous support, autonomous motive, planning behavior, self efficiency, evading intention and evading behavior by applying methods such as hierarchical regression and structural equation model, and revealed the following findings: the students with a physical activity rating lower than 19 points took a percentage of 52.10%, among physical exercise evaders, the female students took a percentage of 56.40%, which was higher the male students’; the autonomous support, relative autonomous motive index, planning behavior variable, and sense of self efficiency of physical exercise evaders were all lower than those of physical exercise doers, while their evading intention and evading behavior were all higher than those of the doers; all the said variables can significantly predict evading intension and evading behavior, in which such 2 variables as subjective norm and sense of subjective behavior control had the greatest effects on evading intention; the established evading behavior path model can respectively explain 40%(male) and 37%(female) of evading intention, as well as 9%(male) and 14%(female) of evading behavior, multi-group analysis indicates that the model does not have gender difference. The said findings indicate the followings: middle school students have a quite serious physical exercise evading behavior; among the evaders, females’ percentage is higher than males’; the established model can explain the causes for middle school students’ physical exercise evading behavior to a certain extent.