According to the sixth Children’s Physical Health Survey, Chinese college students’ health parameters are all off-grade, which may have negative impact on their comprehensive physical quality. In order to improve college students’ physical fitness, college teachers should adopt proper measures to lead students to participate physical exercises to improve their health. Aerobic exercise is a good way to improve physical fitness comprehensively. This essay focuses on three aspects of impacts on college students, namely the theories of aerobic exercise and its conduct range, the theory and the sample researches. In order to be more scientific, the essay adopted three research methods to explain that aerobic exercise has impact on blood pressure, heart, arteries and nervous system, including theoretical approach, experimental approach and data analysis approach. Both the theories of aerobic exercise and its conduct range and the theories are summaries of previous research materials and get our own results. To ensure the correctness of previous researches, the essay uses exact scientific experiments to show the impact of aerobic exercise on blood pressure, heart, arteries and nervous system. This essay will also explain aerobic exercise affects college students’ fitness in the aspect of effectiveness, differences and sustainability. If college teachers have good understandings about aerobic exercise and lead college students to exercise effectively, college students’ fitness will be improve comprehensively.