A guava leaf rich in soluble polyphenols and flavonoid aglycones, a preparation method therefor, and an application thereof. Guava leaf parts are obtained by draining, drying, triturating, and sifting cleaned guava leaves; after the guava leaf parts are mixed with water, the pH value is adjusted, and then an enzyme is added for carrying out an enzymatic hydrolysis reaction; and after completing the system of enzymatic hydrolysis reactions, drying is performed to obtain a guava leaf product rich in soluble polyphenols and flavonoid aglycones. A guava leaf tea obtained using the preparation method has a greatly improved soluble polyphenols content, and flavonoid glycoside components of guava leaves are degraded into flavonoid aglycones with stronger functional activity, the content of aglycones such as quercetin and kaempferol is improved, the anti-oxidation and anti-DNA damage effect of guava leaves are enhanced. Thereby, the guava leaf rich in soluble polyphenols and flavonoid aglycones has great potential fo
