The invention discloses a load emergency adjusting method and a load emergency adjusting device for a thermal power generator unit in an AGC manner. The load emergency adjusting device can flexibly and quickly adjust adjusting rate of the thermal power generator unit. The load emergency adjusting device is characterized in that the load emergency adjusting device comprises an analog quantity signal gatherer S which is used for acquiring a main steam pressure offset, a high-and-low-limit alarm module HLALM, a switching quantity signal gatherer DI, a logic not module, a logic or module, an RS trigger, an analog quantity switching device AXSEL, a multiplexer MUL, an A2 function generator and an A1 function generator; the output of the switching quantity signal gatherer DI is divided into two paths; one path is connected with the setting end of the RS trigger, and the other path is connected with the input end of the logic or module through the logic not module; the output end of the RS trigger is successively connected with the analog quantity switching device AXSEL and the multiplexer MUL; and the A2 function generator and the A1 function generator are respectively connected with the input end of the switching quantity switching device AXSEL and the input end of the multiplexer MUL.