Abstract: The paper introduced basic principle of energy saving with high-voltage frequency conversion speed regulation of exhaust fan, and reformation scheme and effect of energy saving with high-voltage frequency conversion speed regulation in Dong’er air shaft. The frequency conversion speed regulation system of exhaust fan of Dong’er air shaft used “one driving two” manual bypass mode which uses a frequency convertor to drive motors of two fans with one running in variable frequency and the other running in power frequency. The running result showed the scheme saved energy of about 62%.