Abstract: Objective To explore the correlation between MRI quantitative enhancement parameters and prognostic factors and molecular typing of breast cancer and its clinical application.Methods This study was a retrospective study.126 patients with breast cancer who were treated in our hospital from August 2016 to August 2017 were selected.According to different imaging methods，the control group（CT examination）and the research group（MRI examination）were 63 cases each.Retrospective analysis of clinical data of two groups.Results The sensitivity and accuracy of the diagnostic method in the study group were significantly higher than those in the control group（P<0.05）.The volume transfer constant and rate constant of patients with positive estrogen receptors were significantly higher than those of negative estrogen receptors（P<0.05）.The volume transfer constants and rate constants of Luminal type A and Luminal type B were significantly smaller than those of HER-2 overexpression type and TNBC type（P<0.05），but the volume ratio of extravascular extracellular space of Luminal type A and Luminal type B was significantly larger than that of TNBC type.（P<0.05），in which Luminal B type had the highest extravascular extracellular space volume ratio，while TNBC type had the highest rate constant.Conclusion Quantitative enhancement parameters of MR imaging have certain implications for the prognosis and molecular typing of breast cancer，and have certain correlation with estrogen receptor，but not with human epidermal growth factor receptor-2，which is worthy of clinical promotion.

Key words: MRI quantitative enhancement parameters, breast cancer prognostic factors, molecular typing, correlation