The aim of this study was to investigate the usefulness of whole body MR imaging (WB-MRI) in the detection of bone metastases from breast cancer and to compare the results with those from bone scintigraphy. In 21 patients with suspected bone metastasis from breast cancer, both bone scintigraphy and WB-MRI were performed. With WB-MRI, coronal images were obtained using a body coil in an FOV of 48 cm, and sequences of fast short TI inversion recovery (STIR) and gadolinium-enhanced fast spoiled GRASS (SPGR) were used in three parts: from the head to the thorax, the abdomen to the pelvis, and the lower extremities. Of the total 105 metastatic bone lesions, 65 (61.9%) were detected by bone scintigraphy, 98 (93.3%) by fast STIR, and 74 (70.5%) by fast SPGR. Thus, the detection of bone metastases by WB-MRI was excellent. However, detectability in the ribs was lower for WB-MRI than for bone scintigraphy. Contrast-enhanced MRI was useful in the differentiation of osteosclerotic lesions, in which high signal intensity is rare, pleural effusion, which has high signal intensity on STIR, and bone metastatic lesions. In conclusion, WB-MRI showed high reliability in the detection of bone metastatic lesions from breast cancer.