Abstract: A preparation method of a Mn-MOF-based cold-adapted nanozyme and a preparation method thereof. The method includes: preparing a Mn(CH3COO)3·2H2O solution by fully dissolving a manganese-containing precursor Mn(CH3COO)3·2H2O in a mixed solution of an alcohol and distilled water; wherein the alcohol is ethanol or methanol; preparing a benzenetricarboxylic acid solution by fully dissolving benzenetricarboxylic acid solid in the mixed solution of the alcohol and distilled water; reacting the Mn(CH3COO)3·2H2O solution with the benzenetricarboxylic acid solution sufficiently using co-precipitation; and centrifuging and removing a supernatant to obtain the MnBTC, where the MnBTC is nano-metal-organic framework (nano-MOF) with a particle size of less than 10 nm.