Since the first triboelectric nanogenerator (TENG) was developed in 2012, TENG now has become an energy technology to efficiently convert the mechanical energy into electricity. By using TENG as a power source, numerous self-powered sensing systems toward different targets have been demonstrated and showed their potential. In this study, we used TENG to replace the traditional power source to synthesized different metal nanoparticles in the electrochemical system. The carbon fiber fabrics were adopted as the conductive substrates to grow nanoparticles. The size and density of nanoparticles on the carbon fiber fabrics can be controlled by the electric output from the TENG. In addition, we also showed that the as-prepared carbon fiber fabrics were integrated with TENG and then became a self-powered sensing system. The system exhibited good selectivity and sensitivity toward lactate detection. In addition, the sensing part in the system was designed to be flexible in order to fit the curve of human body. Finally, the self-powered sensing system was successfully demonstrated to detect the lactate concentration in perspiration. In the near future, this device will help people to control their physical function and health immediately. We also believe that it can offer considerable promise for diverse sport, military, and biomedical applications.