Diffusion-weighted imaging (DWI) yields qualitative andquantitative information that reflects tissue cellularity and cell membrane integrity, which complements the morphologic information obtained by conventional MR imaging. At present, there is no role of DWI in the characterization or local staging of primary bone tumors. However, whole body DWI has a potential role in assessment of bone metastases and distant staging .DWI also has a great success in the differentiation between benign and malignant vertebral compression fractures.DWI could provide earlier identification of patients with a poor treatment response or of those with tumor recurrence. This is because cellular death and vascular changes in response to treatment precede changes in lesionsize, Therefore, DWI could provide an opportunity to adjust individual treatment regimens more rapidly, sparing patients the unnecessary morbidity, expense, and delays in the initiation of effective treatment .Whole-body DWimaging is an attractive lesion detection technique because it enables “at-a-glance” assessments, where one’s attention is immediately drawn to potential abnormal regions, which helps reduce the image interpretation times of anatomic whole-body MR imaging . There are several clinical applications for DWIBS have been reported in the literature, especially for oncological imaging.