With the development of industrial automation and intelligence, higher demands have been placed on the accuracy, reliability, and real-time capability of flow measurement. This paper provides a brief overview of the basic principles of flow measurement, categorizes existing flow meters based on the principles of flow measurement and the structural principles of flow meters, and summarizes the advantages and limitations of common flow meters. Building on this foundation, the paper further analyzes the current research directions in flow measurement technology, focusing primarily on flow meter performance optimization, pipeline fluid dynamics research, and fluid dynamic system research, and summarizes the research status in these areas. Additionally, it introduces the latest research findings from the author’s research group on refined ammonia injection flow control for denitrification. Finally, it addresses current issues and challenges in the application and development of flow measurement technology across various fields.