Abstract: Invasive or infiltrative lobular carcinoma (ILC) of the breast is a common type of breast cancer with distinctive morphology, molecular features, and peculiar clinical manifestations. The morbidity of the disease progressively increases annually. Over the past years, the variants of ILC gradually gained recognition. Moreover, based on the studies on the features of the breast cancer gene, differential expression of other genes were found in addition to the E-cadherin gene. The progress in the studies on the clinicopathologic features and molecular pathology of ILC of the breast was reviewed in this article.