The present invention relates to medium materials for MALDI, and in particular relates to application of submicron carbon oxide balls as a medium in MALDI-MS. In the present invention, the submicron carbon oxide balls are used as the MALDI-MS medium, a defect of medium interference when a conventional organic medium is used is solved, the accurate analysis of various compounds with molecular weight less than 1000 Dalton, such as amino acid amino acids, lipid compounds, polypeptides, oligosaccharides and drugs can be fast and efficiently achieved. The submicron carbon oxide ball medium related in the present invention can be prepared by using a simple and controllable method, is regular in morphology, uniform in size, low in cost, and good in water solubility, and overcomes a problem that the dimension is controlled difficultly so as to influence stability of mass spectrometric detection when carbon-based materials such as carbon nano tubes and graphene are used as the MALDI medium, thus being an optimized medium capable of assisting MALDI-MS to achieve high-sensitivity and high-throughput analysis on the compounds within a low molecular weight area.