The article examines the impact of military pentathlon classes on the dynamics of the cadets' physical development and functional status in the training process. The research was conducted at the Department of Military Training of the National Academy of Internal Affairs (Ukraine) in 2019-2020. The research involved 18-25 years old cadets (men), who studied at the department in 1-4 semesters. Two groups of cadets were formed: the experimental group (EG, n = 44), the cadets of which were engaged in pentathlon, and the control group (CG, n = 45), the cadets of which were engaged in the existing method of physical training. The research of indicators of the cadets' physical development and functional status was carried out on such indicators as body height, body mass, dynamometry of the hands, heart rate, arterial blood pressure, vital capacity of the lungs and design indices. The research methods included analysis of literature, pedagogical observation, medical and biological methods, and methods of mathematical statistics. The positive effect of military pentathlon on the cadets' physical development and functional status was established. At the end of the research, the EG cadets had significantly better indicators of body mass, vital capacity of the lungs, heart rate at rest, vital index, Robinson index and heart rate recovery time after exercise than the CG cadets. In general, the results suggest that the achieved level of the cadets' physical development and functional status engaged in military pentathlon will in the future improve the efficiency of their professional and service activities.