OBJECTIVES: The aim of this study was to evaluate cost-utility of vacuum-assisted biopsy (VAB) for diagnosis of breast cancers compared with conventional core needle biopsy (CNB) in China from societal perspective. METHODS: A decision tree model was built to measure QALYs obtained over a 5-year horizon of patients with suspected breast cancers after initial diagnosis with two biopsies. The fundamental assumptions were the differences of sensitivities and false negative rates between VAB and CNB would result in disease progression and delay treatments in different degree, which would further affect 5-year survival rates and life quality of breast cancer patients. Direct medical costs were obtained from 5 tertiary hospitals in China. Sensitivities were estimated from a meta-analysis performed by our group. 5-year survival rates and EQ-5D index scores of Chinese breast cancer patients classified by TNM staging system were derived from published literature. One-way sensitivity analysis was conducted. RESULTS: Direct medical costs of VAB and CNB were 5,172.38 CNY (95%CI, 4,679.79, 5,664.97) and 535.78 CNY (95%CI, 465.24, 606.32) respectively. The sensitivities of VAB and CNB were 95.76% (95%CI, 91.88%, 97.83%) and 89.20% (95%CI, 76.88%, 95.35%). Cost-utility analysis showed that when missing breast cancers upgrading from stage 0-Ⅰ or Ⅱ to stage Ⅲ or Ⅳ, incremental cost utility ratios (ICUR) were lower than per capita GDP (53,980 CNY). When upgrading from stage 0-Ⅰ to stage Ⅱ or from stage Ⅲ to stage Ⅳ, ICUR values were higher than per capita GDP but lower than 3 times of per capita GDP (161,940 CNY). Sensitivity analysis revealed that sensitivities of VAB and CNB were major sources of uncertainty, especially the latter one. CONCLUSIONS: In Comparison with CNB, VAB is more accurate but much more expensive. VAB is more likely to be cost-utility when missing breast cancers upgrading from early stages to advanced stages.