The invention relates to the technical field of modified starch and application thereof and particularly relates to modified starch for dried-fruit film forming, a preparation method therefor and an application of the modified starch. A preparation process of the modified starch comprises the steps of regulating the pH of native starch slurry to be alkaline, then, carrying out heating, then, adding 2-4 parts of oxidant, carrying out an oxidation reaction, then, adding 3-5 parts of vinyl acetate as an esterification reagent, and controlling esterification time to be 2 to 4 hours. The prepared modified starch is low and stable in viscosity, transparent in paste, low in retrogradation, high in film forming property and good in film forming performance and is applicable to dried-fruit film forming; and dried-fruit film forming slurry prepared by using the modified starch disclosed by the invention can form a layer of uniform, dense and tightly-bonded starch film on the surface of each dried fruit, dried fruits can be effectively prevented from becoming mildewed, meanwhile, the effects of increasing quantity, increasing weight and improving brittleness are achieved, and the economic value of the dried fruits is increased.