Abstract: Metrology is the science of measurement and its applications, which encompasses all aspects of the theory and practice of measurement. The purpose of metrology is to ensure the consistency of units and the accuracy and reliability of measured values. As one of the ten metrological specialties, ionizing radiation metrology studies the interaction theory of ionizing radiation with matter and measures the physical quantities characterizing radioactive sources or radiation fields and the interaction of ionizing radiation with matter. China Institute of Atomic Energy (CIAE) has developed for more than forty years in the field of ionizing radiation metrology and test technology, and achieved the numerous achievements which have provided strong metrology guarantees for the national construction and development of our country. In this paper, the development history of ionizing radiation metrology at CIAE was briefly reviewed, and the development status and the obtained achievements in the last decade were emphatically presented. Through the analysis of the current national demand situation and the development of science and technology, the future development trends, main problems and corresponding solutions of ionizing radiation metrology were elaborated upon. The progress made in the discipline construction of ionizing radiation metrology at CIAE and the gap with advanced metrology institutions abroad were summarized, and some suggestions for future development were put forward.