We report 2 cases of malignant lymphoma of the breast which were clearly shown on total body imaging as well as on SPECT with Ga-67 and Tc-99m MIBI. Tumor accumulation of Ga-67 was seen in all cases including a recurrent tumor. Ga-67 scintigraphy is useful for follow up in detecting relapse, as well as in predicting responses to therapy. Tc-99m MIBI was found to accumulate in the malignant lymphoma of the breast, and especially SPECT images of breast lesions provided better contrast than planar images, and Tc-99m MIBI SPECT could diagnose localization of the tumor because there was no uptake by the breast. But the Tc-99m MIBI accumulation of the tumor was lower than Ga-67.