The invention discloses a wide-load condensate throttling frequency modulation method of a thermal power generating unit. When condensation pump variable frequency instructions do not reach a lower limit on a high-load section, condensate variable frequency instructions are reduced, the condensate flow is reduced, the steam extracting quantity of a steam turbine regeneration system is correspondingly reduced, and the unit load is increased; and when the unit is located on a low-load section or the condensation pump variable frequency instructions reach the lower limit, the openness of a deaerator main valve is reduced, the condensate flow is reduced, the steam extracting quantity of the steam turbine regeneration system is correspondingly reduced, and the unit load is increased to achievecondensate throttling once frequency modulation function of a wide-load section. The method can solve the defects in the prior art, and realizes the condensate throttling variable frequency modulationin the whole AGC wide-load section of the unit.