Breast cancer is the second leading cause of death all over the globe among women. Nanotechnology has emerged recently to overcome the limitations of the traditional drug delivery system. Conventional chemotherapies have several side effects that damage the immune system and other organs. Several other cancer treatments cause the proliferation of normal cells, making them cancerous due to nonspecific targeting, inability to enter the core of the tumor, and poor solubility. To overcome the problems of chemotherapies, nanotechnology has come up with the direct killing of a tumor cell with fewer side effects. Nanoparticles are designed to recognize the cancer cells and provide accurate drug delivery without interacting with the healthy cells. The use of nanoparticles with anticancer drug therapies has shown promising effects in the killing of cancer cells. The major objective of this review is to discuss the role of Heat Shock Protein 90 (Hsp90) in breast cancer and its treatment by targeted therapy via nanotechnology. This review covers research published since 2001 describing the nanotechnology mediated Hsp90 targeted breast cancer therapy.