The invention relates to an essence spice and a preparation method thereof, in particular to an isatis root extract essence spice for cigarette and preparation method thereof. The preparation method comprises the following steps: adding isatis root in water to perform refluxing and extracting and adding sugar to perform Maillard reaction and obtain the product at the same time, wherein the refluxing and extracting process is performed in two steps, in the first step, 5 times of water is added to perform refluxing and extracting for 3-5h, in the second step, 3 times of water is added to perform refluxing and extracting for 0.5-2h and in the two steps of the refluxing and extracting process, 5g-20g of sugar is added to perform Maillard reaction. The isatis root extract essence spice used asbottom material can be added in the cigarette to improve the quality of the cigarette and increase the thickness and abundance of the perfume of the cigarette, and the drug effect can reduce the bad effect of the cigarette.