In this study we assess early changes following 90Y radioembolization (RE) in hepatocellular carcinoma and liver parenchyma using MR elastography and predict response at 6 weeks/6 months. Tumor stiffness (TS) and liver stiffness (LS) adjacent to the tumor were significantly increased 6w following RE. Baseline TS and LS adjacent to the tumor were significantly lower in patients who achieved complete response. Baseline TS correlated with necrosis at 6w and was a significant predictor of partial response or stable disease based on mRECIST criteria following RE. MR elastography may be a useful tool for predicting necrosis and tumor response to RE.