Molecular subtype classification of breast tumor is of paramount importance in determining aggressiveness and prognosis. The ability to use diffusion weighted imaging (DWI) for the prediction of molecular subtypes may improve management in breast cancer. In this study, two radiologists retrospectively evaluated different metrics on apparent diffusion coefficient maps of 107 patients with invasive breast cancer. ER and PR positive lesions had lower ADC values while HER2 positive and high-proliferating had higher values. Luminal cancers had lower ADC values than other subtypes, thus DWI may be used to predict tumor subtype in breast cancer.