Abstract: By using the methods such as literature and comparative study, this paper made a comparison on the health monitoring and subsequent intervention of youngsters between China and the US, and the results showed that the American teenagers' physique monitoring had 3 characteristics: scientific nature and effectiveness of the standard, systematization and directivity of management, as well as the scientific advancement of its electronic application. In the intervention stage of follow-up monitoring, according to the feedback of youth physique monitoring, America made a targeted plan for physical activity and health improvement, which were characterized by non-governmental organizations' active participation and multidimensional intervention, and America paid more attention to the feedback and instruction of monitoring information, set up prize for monitoring of different parts, fitness, active lifestyle awards and other different forms of incentive mechanism. We suggested paying attention to evaluate fitness scientifically and strengthening physique report as well as comprehensive assessment of physical activity, accelerating the electronic application technology, creating governmental social forces to participate in physique monitoring follow-up intervention, carrying out the sunlight sports, adapting and promoting the further development of adolescent physical activity and health promotion plan, and perfecting the function of physique monitoring feedback and monitoring after the reward incentive system.