A method for relieving memory dysfunction using Puerariae Radix Extract is provided, including decocting Puerariae Radix in water, concentrating the extracted product thereof, and administrating an effective dose of the Puerariae Radix extract to a subject. Since the present invention merely uses Puerariae Radix as an ingredient, it belongs to a Chinese herbal medicine of single drug prescription. Further, with the same amount of Puerarin, Puerariae Radix Extract of the present invention provides a better neuroprotective effect in comparison with Puerarin, which indicates that the Puerariae Radix extract contains more active neurotrophic ingredients other than Puerarin. Therefore, Puerariae Radix extract is more promising potential therapeutic medicine than Puerarin for relieving the symptoms of anxiety and cognitive impairment.