The invention belongs to the technical field of a medicine, and particularly relates to a coumarin compound with antioxidant activity, a preparation method of the coumarin compound, and an application of the coumarin compound to prepare a medicine for neuroprotection, tumor resistance, anticoagulation, radiation resistance, and inflammation resistance. The coumarin compound has a general structural formula shown in the description. Each of R1 and R2 is one of H, alkyl, alkoxy, hydroxyl, halogen, nitro, cyano, carboxyl, and ester. The coumarin compound is prepared by taking ethanol or acetic acid as a solvent and by reaction of three components of 4-hydroxycoumarin and a substitute of 4-hydroxycoumarin, 1- cyanoacetylguaiazulene and aromatic aldehyde. The preparation method is simple to operate and high in yield of a target product, has a good elimination effect on free radicals, and is suitable for mass production.