The invention provides a fuzzy control method, controller and control system of lime white injection amount. The fuzzy control method of lime white injection amount includes the steps: detecting the input amount to obtain the detected input amount; calculating the deviation between the detected input amount and the given value, and the deviation change rate, and taking the deviation and the deviation change rate as the input variables of fuzzy control; and obtaining the output variables of fuzzy control, based on the input variables of fuzzy control, wherein the change rules of the output variables are that when both the deviation and the deviation change rate are high values, the output variables are low values; when the deviation is a high value and the deviation change rate is a low value, the output variables are intermediate values; when the deviation is an intermediate value and the deviation change rate is a high value, the output variables are low values; and when the deviation is a low value, the output variables are high values. The fuzzy control method of lime white injection amount can more accurately simulate a human brain to process the fuzzy information, thus being more artificially intelligent, being able to improve the utilization rate of lime white, reducing unnecessary material consumption and material accumulation, and saving the cost.