A preparation method of tetraboronic acid compounds includes mixing aldehydes with amines and dissolving them in a solvent to obtain a first solution, stirring the first solution, adding carboxylic acid and isocyanide to obtain a second solution, heating the second solution to obtain a first product, extracting and purifying the first product to obtain tetraboronate ester compounds, and executing a deprotection reaction on the tetraboronate ester compounds under heating by microwave to obtain a second product. The second product contains tetraboronic acid compounds, and the tetraboronic acid compounds have the structure as shown in formula (I).
