Abstract: Objective To investigate the role of whole-body diffusion-weighted imaging (WBDWI) in the detection,diagnosis and assessment of curative effect of metastatic tumors. Methods WBDWI by GE Signa HD xt 3.0 T MR Scanner was performed in 38 patients with metastatic tumor.The positive results were analyzed and diagnosed by two deputy chief physicians with double-blind method,the apparent diffusion coefficient (ADC) values of the lesions were measured on ADC imaging,and the region of interest (ROI) was 20 mm². Results A total of 38 patients with metastatic tumor were examined by WBDWI,of which,2 cases had been done for 4 times,and another 2 had been done for 2 times.The WBDWI imaging of metastatic tumors showed multiple abnormal signal lesions in the whole body,including 38 cases of multiple lymph nodes enlargement in the body,13 cases of multiple abnormal signals and 5 of solitary in liver,3 in spleen and 7 in adrenal glands,10 in lung nodules,and the diffuse infiltration of bone marrow of vertebrae,pelvis,humerus,scapula,sternum and ribs in 24 cases.The lesions showed nodular and patchy hyper-intensity on WBDWI imaging,hypo-intensity on flipped imaging of WBDWI and ADC imaging.Of 4 cases with follow-up examination after the treatment,2 showed that the number of lesions reduced and the signal intensity decreased on DWI imaging,and the ADC values increased (good curative effect),one showed that the number of lesions increased (poor curative effect),but no significant changes in signal intensity,another one was no significant change in the number of lesions and signal intensity. Conclusion As one systemic functional MR-imaging technology,WBDWI has a certain significance in the comprehensive evaluation of metastatic tumors and lesions.