The invention discloses 2,3,4,5,-tetra(3',4'-dihydroxyl phenyl)thiophene and application of 2,3,4,5,-tetra(3',4'-dihydroxyl phenyl)thiophene as an MALDI (matrix assisted laser desorption ionization) matrix in analyzing small molecules. The analysis method using 2,3,4,5,-tetra(3',4'-dihydroxyl phenyl)thiophene as the MALDI matrix is suitable for performing mass spectrum analysis on the small molecules with m/z being less than 1000. And adaptive molecule varieties comprise amine matters such as amino acids, vitamins, excitants, caffeine, urea, dopamine, melamine, aniline, purines and pyrimidines, etc., wherein background interference is not produced because of only a few fixed background peaks when the method is used for detecting the molecules with m/z being less than 1000. The method for preparing 2,3,4,5,-tetra(3',4'-dihydroxyl phenyl)thiophene provided by the invention can be effectively applied to fields such as the organic and biological mass spectrum, the mass spectrum imaging, the protein spectroscopy, the metabonomics, the biomarker discovery, the environment analysis and the like.