The purpose of this study was to examine the impact of instructional leadership on high school students' academic achievement in the Chinese context and to determine which specific instructional leadership dimensions have the most important role. The sample included 26 high schools with 26 principals and 4288 students in Shenyang, China. The principals rated their instructional leadership according to the Revised Instructional Leadership Questionnaire of China (ILQC-R). The hypotheses were tested using hierarchical linear models. The results indicated that, after controlling for student background, school context, and principal demographics, overall instructional leadership showed a significantly moderating influence on the relationship between high school entrance scores and college entrance scores for students. Regarding the four different dimensions, different influence trends were observed. The dimensions of managing instruction, defining the school mission and goals, and promoting teacher development were found to influence students' college entrance scores in both direct and indirect ways; however, no significant impact on students from managing public relations was found.