Abstract: Boron neutron capture therapy(BNCT), as a highly promising radiotherapy modality, has emerged as a significant treatment option for various malignant tumors, including high-grade gliomas, recurrent head and neck cancers, and melanoma. BNCT is characterized by the nuclear reactions that occur when nonradioactive 10B is irradiated by low energy thermal neutron to yield high linear energy transfer(LET) particles, such as ⁴He and ⁷Li. These particles have high relative biological efficacy and a short path length of approximately the diameter of a single cell(5-9 μm), which enables selective damage to tumour cells marked with ¹⁰B and preserves the adjacent normal tissue. Compared to classical radiotherapies, BNCT has garnered growing attention within the medical community due to its precision targeting, potent biological effects, and short course of treatment. The therapeutic efficacy of BNCT is based on accurately controlling radiation dose, which is mainly determined by the local 10B concentration of tumour and the neutron flux. Currently, BNCT is being implemented in clinical trials. Dynamic and quantitative monitoring of ¹⁰B concentration of boron-containing drugs in intratumor is the key element to realize the “efficiency and side-effect reduction” of BNCT. Consequently, there is an urgent need for the development of more accurate measurement techniques. In this review, we provide a concise overview of the principles underlying BNCT, and summarize various monitoring methods for boron-containing drugs during treatment, including physical, nuclear, chemical, and novel techniques utilizing advanced molecular imaging technologies such as positron emission tomography, magnetic resonance imaging, and optical imaging. Furthermore, we analyze the strengths and limitations of these approaches. We hope this review provides informative insights into the future development of the precise and efficient BNCT.