This article explored the different clusters of leadership styles and the relationship between principal leadership style and student academic achievement in domains of mathematics, reading, science, and collaborative problem-solving in Germany and China. We used PISA 2015 data covering 6,504 students and 256 school principals from German schools and 9,841 students and 268 school leaders from Chinese schools. Results identified three leadership styles in Germany, namely, transformational (23.4%), instructional (41.3%), and integrated (35.3%) leadership, and two leadership styles in China, namely, transformational (38.6%) and instructional (61.4%) principals. Principals with instructional and integrated leadership had higher student achievements in Germany, whereas only principals with transformational leadership had slightly higher student achievements in China. Moreover, three leadership styles in Germany and two in China showed their relationships with each domain of student achievement. In conclusion, principals in Germany and China had different priorities in leading schools. The differences that principal leadership made on student achievements highlighted the differences in principals' situational context and leading characteristics between Germany and China.