PURPOSE: To investigate whether a correlation exists between the semi-quantitative breast-specific gamma imaging (BSGI) findings and dynamic contrast-enhanced (DCE) MRI parameters assessed by a computer-aided evaluation program. MATERIALS AND METHODS: Semi-quantitative index of the lesion to non-lesion (L/N) ratio in BSGI and DCE-MRI parameters was assessed by a computer-aided evaluation program, where 47 cases of invasive breast cancer were obtained. Correlations between the L/N ratio and DCE-MRI parameters were assessed by a computer-aided evaluation program. Tumor diameter (cm), angio-volume (cc), degree of initial peak enhancement (%), persistent enhancement proportion (%), and washout enhancement proportion (%) were analysed. The relationships between the L/N ratio and DCE-MRI parameters were evaluated by a univariate and multivariate regression analysis. RESULTS: The mean L/N ratio of the 47 tumors was 3.63 ± 2.19 (range: 1–13.1). The L/N ratio was higher in tumors with larger diameters (p < 0.001), increased angio-volume (p < 0.001), higher degree of initial peak enhancement (p = 0.005) and increased washout enhancement proportion (p = 0.004). In the multivariate regression analysis, angio-volume (cc) and washout enhancement proportion (%) were associated with L/N ratio (p = 0.007 and p = 0.024, respectively). CONCLUSION There was a correlation between the semi-quantitative L/N ratio in BSGI and DCE-MRI parameters assessed by a computer-aided evaluation program for breast cancer.