Background: Currently employed techniques for the localization of nonpalpable breast lesions suffer from various limitations. In this paper, we report on 2 patients in order to introduce an alternative technique, indocyanine green fluorescence-guided occult lesion localization (IFOLL), and determine its applicability for the surgical removal of this type of breast lesions. Case Reports: Preoperatively, one of the patients had a needle biopsyproven diagnosis of breast cancer, and the other one had suspicious findings for malignancy. Lesion localization was performed within 1 h before surgery under ultrasonography control by injecting 2 ml and 0.2 ml of indocyanine green into the lesion and its subcutaneous tissue projection, respectively. During surgery, the site of skin incision and the resection margins were identified by observing the area of indocyanine-derived fluorescence under the guidance of a near-infrared-sensitive camera. In both cases, the breast lesion was correctly localized, and the area of fluorescence corresponded well to the site of the lesions. Subsequent surgical excision was successful with no complications. On histopathologic examination, the surgical margins were found to be clear. Conclusion: IFOLL seems to be a technically applicable and clinically acceptable procedure for the removal of nonpalpable breast cancer.