The invention relates to the technical field of neurology, in particular to a medicine for treating neurasthenia, which comprises the following components (by mass percentage): trimetazine: 2-4%, midecamycin: 1-5%, teabutemetone : 30-40%, Taurine: 15-17%, Ketotifen: 2-6%, Catechin: 23-25%, Niacinamide: 3-5%, Oleanolic acid: 1-3% , Quetiapine: 1.5-2.5%, Loxoprofen: 2.5-11.5%. The invention also discloses a preparation method of the drug, which includes the following steps: step 1: preparing materials, step 2: drying and grinding into powder, step 3: pulverizing, step 4: preparing ethanol solution, step 5: concentrating and drying, and step 6 : extract medicine. The invention can effectively improve body function and immunity, has significant curative effect on treating neurasthenia, has no toxic and side effects on human body, can relieve anxiety and cognitive deficiency symptoms, and has the effects of clearing away heat and fire, regulating qi and dredging collaterals.