Abstract: The incidence rate of prostate cancer (PCa) ranks first among all male tumors, and PCa is prone to bone metastasis, which is characterized by pain, decreased quality of life, fractures, bone functional decline, impairment of hematopoiesis, and reduced survival rate. Bone scan index (BSI) is a method to quantitatively measure the severity of bone diseases. It can not only quantitatively evaluate the degree of bone tumor involvement in PCa patients, but also incorporate fully quantitative assessments of disease burden in associating bone scintigraphy post-treatment changes with clinical examination outcome, to assess progression or remisson of disease. In this paper, BSI, the development of automated BSI and its research in PCa are reviewed to provide reference for clinical practice.