The invention provides a method for inhibiting 
peroxidase activity by using fluorescent 
graphene quantum dots. The method comprises the following steps: (1) adding a 
carbon source into a certain amount of water to prepare a 
mixed solution, heating the solution until the 
moisture is completely evaporated, transferring the solution into a 
high pressure reactor, heating and reacting for a period of time, dissolving the product in water, regulating the pH value of the 
system to be neutral by using alkali liquor, purifying the product, and 
drying, thereby obtaining 
solid graphene quantum dots; and (2) dispersing the 
quantum dots obtained in the step (1) in secondary 
distilled water, taking a proper amount of 
quantum dot solution and 
enzyme solution, adding the solution into a 
buffer solution, adding a color developing agent and H2O2 after a period of time, uniformly shaking the 
mixed solution, rapidly adding the solution into a 
cuvette, measuring the light absorption value of the maximum absorption 
wavelength of the product on an 
ultraviolet-visible spectrophotometer, and performing blank sample control, thereby determining the relative 
enzyme activity. The 
graphene quantum dots are prepared by adopting low-price and readily available raw materials, and the method is green and environment-friendly. The structure of the 
enzyme can be changed by virtue of the interaction between the graphene quantum dots and zymoprotein, and regulation of the enzyme activity is realized.