Sentinel lymph node biopsy (SLNB) is an important surgical advance in the management of early breast cancer. Localization of the sentinel lymph node (SLN) in breast cancer and other cancer patients is widely used now utilizing isosulfan blue dye. Few alternative types of dye have been used and investigated. In a prospective study of 54 patients, methylene blue dye was used as an alternative to isosulfan blue to localize the SLN in breast cancer patients. The methylene blue dye technique was successful in 91.1% of patients after excluding the initial learning cases; the results are similar for isosulfan blue dye. This study describes methylene blue dye localization as a successful alternative to isosulfan blue dye in identifying the sentinel node in breast cancer patients. Methylene blue dye is readily available in most Egyptian institutes, with a very low cost.