The invention discloses a medicinal composition for treating dizziness, headache, neural headache and migraine caused by cerebral thrombosis, hypertension, cerebral arteriosclerosis, cervical spondylosis and the like and a preparation method thereof. The medicinal composition is prepared from the following raw materials in part by mass: 20 to 180 parts of kudzuvine root, 10 to 70 parts of Szechuan lovage rhizome, 10 to 50 parts of gambir plant and 10 to 70 parts of root of red-rooted salvia. The method for the medicinal composition comprises the following steps of: decocting the raw materials for preparing the medicinal composition by adding water, extracting the decoction, collecting filtrate, concentrating the filtrate to obtain thin paste, adding 60 to 90 percent ethanol into the thin paste so that the ethanol content reaches 30 to 60 percent, standing the mixture, taking supernate and reclaiming all ethanol to obtain thick paste, drying the thick paste, crushing the dried thick paste to obtain powder, and preparing the powder into capsules or tablets and the like. Clinical experiments show that the medicinal composition has the effects of activating blood, dissolving stasis and dredging the channel, and is used for treating dizziness, headache, neural headache and migraine caused by cerebral thrombosis, hypertension, cerebral arteriosclerosis, cervical spondylosis and the like. The medicinal composition can improve cerebral ischemia and cerebral blood supply insufficiency, is favorable for recovery of neural function, enhances the memory, and can improve the blood circulation of the lower limb and enhance the activity of the lower limb.