The invention provides a virtual synchronous machine excitation adjustment method based on adaptive droop control. Aiming at an existing virtual synchronous machine voltage control method, improvementis performed, and an adaptive droop control method is introduced to adjust the output voltage of a virtual synchronous machine. The method is characterized by firstly, establishing the equivalent model of the virtual synchronous machine and a power grid interface; and secondly, constructing a virtual synchronous machine excitation adjusting module, inputting a detected load change condition intoan adjusting unit, correcting and calculating a droop control coefficient, acquiring a corrected and calculated voltage deviation instruction and outputting to the virtual synchronization machine so as to achieve the adjusting effect of a virtual synchronous machine port voltage. Under the effect of the improved droop coefficient, the virtual synchronous machine port voltage can be maintained in areasonable range so that the adaptive adjusting target of a voltage response load fluctuation is realized.