The scientific classification of pressure vessels serves as the basis for differentiated safety supervision and holds great significance to the safety of equipment and the economic benefit of the industry. The current classification methods for pressure vessels in China, the European Union and the United States have been systematically sorted out from the dimensions of design and fabrication, administrative licensing, and use management. The control requirements for various types of pressure vessels in different regions have been summarized, and the classification logic and control system differences among the three have been revealed through multi-dimensional comparisons. It is found that, currently no differentiated requirements are set for the design, fabrication, inspection, use management and administrative licensing of the Ⅰ and Ⅱ category pressure vessels in China, which leads to the lack of practical regulatory significance of this hierarchical classification. To address this issue, optimization recommendations are proposed from dimensions including the refinement of the regulatory framework and the elaboration of technical standards, thereby offering references and insights for the advancement and perfection of China’s pressure vessel classification system.