The signaling pathways activated by the steroid hormone oestrogen include a variety of cytoplasmic second messengers linked to a multitude of tissue-specific effects. In thelast decade, sphingolipids and their membrane receptors were added to the list of oestrogenactivated mediators. Oestrogen triggers the sphingolipid signalling cascade in varioustissues including breast cancer. Extensive research has shown that sphingolipids are thekey regulatory molecules in growth factor networks. Sphingolipids can control the rate of cell proliferation and the differentiation outcome during malignant transformation. In this study, we summarise novel experimental evidences linking sphingolipids to oestrogenactivated effects, highlight the role of sphingolipids in cancer cells and discuss new avenues for future research at the intersection between oestrogen and sphingolipid signalling.