Traditional research and development (R&D) modes relying on empirical trial−and−error struggle to meet the development needs of the process industry under the national carbon goals. In contrast, mesoscience can provide important theoretical support for the high-end, intelligent, and green development of the process industry. "Mesoscience−enabled one−step scale−up of multiphase reactors from laboratory to industrial scale" was selected as one of the Top Ten Engineering and Technical Challenges of 2024 by the China Association for Science and Technology, highlighting the scientific value and engineering significance of this research direction. This paper explores the role of mesoscience in revealing the dynamic evolution of mesoscale structures and its theoretical support for precise material design, one−step scale−up of reactor, and process intensification. It systematically analyzes key bottlenecks restricting development, including insufficient systematic research on mesoscales, lagging development of independent industrial software, resistance in technology transformation, and low enterprise participation hinder its progress. Furthermore, countermeasures such as strengthening top−level design and policy support, deepening theoretical research on mesoscience, accelerating the construction of independent software and hardware systems, and promoting industry−academia−research collaborative are proposed. These measures will facilitate breakthroughs in one−step scale−up of multiphase reactors, support the green and low−carbon transformation of process industry, and contribute to achieving national carbon goals.