The natural frequency of the micro piezoelectric vibration generator has been defined when the generator is manufactured. When the natural frequency of the micro piezoelectric vibration generator is inconsistent with the frequency of vibration source, output power will sharply decrease, and it cannot normally supply power. In order to make the natural frequency of the generator approach the frequency of vibration source, on the basis of the relationship between the piezoelectric capacitance and the Young\'s modulus, the author adopts capacitance frequency modulation technology to turn the bending stiffness of the cantilever beam and the natural frequency of the micro piezoelectric vibration generator. At the same time, adjusting the size of the cantilever tip mass, it can enlarge the piezoelectric generator frequency range, and the piezoelectric generator has a wide operating frequency. Experimental results show that the natural frequency of the piezoelectric generator reduced from 69.8Hz to 46.5Hz after the mass is added at the end of the cantilever beam. When the bypass capacitance varies from 0nF to 30nF, the natural frequency of the generator can be continuously adjusted from 46.5Hz to 42.4Hz. When the frequency in reality is smaller than the natural frequency of the piezoelectric vibration generator, the methods can make the natural frequency approach the frequency of vibration source.