Methyl methacrylate (MMA) is an important bulk chemical that can be used to produce plexiglasses, functional polymers, coatings, and so on. The C3/C4 method based on petrochemical and coal chemical feedstocks is considered a green process for the production of MMA, and the oxidation of methacrolein (MAL) to methacrylic acid (MAA) is a key step in this process, focusing on the summary and analysis of the catalysts used to catalyze this reaction. The catalysts based on phosphomolybdenum vanadate of Keggin structure currently used in industry are introduced, the active species, the role of different components, the loaded catalysts and the current problems were summarized and the corresponding solutions were proposed. The research progress of non-metallic carbon-based catalysts that can catalyze the reaction was introduced, and the current deficiencies and possible solutions were pointed out, and it is believed that the future research of non-metallic carbon catalysts should be carried out in the following aspects: 1)Designing and preparing carbon catalysts with high activity and stability; 2)Constructing the catalyst structural model by using characterization; 3)Investigating the mechanism of carbon catalysts through in situ experiments, isotope tracking experiments, computational simulations, and kinetic experiments to explore the carbon catalytic mechanism.