In this article, we investigate the value of T1rho MRI in monitoring CCl4-induced liver injury, staging liver fibrosis and grading inflammation activity in a rat model. Forty-one model rats underwent black blood T1rho MRI in multiple time points, and eleven normal rats selected as control group. Liver T1rho values were measured in different time points and compared between different fibrosis stages and inflammation grades. Our result showed that T1rho MRI can be used to monitor CCl4-induced liver injury. Changes of liver T1rho values were the result of a combination of liver fibrosis and inflammation activity, and inflammation activity had a greater impact on liver T1rho values than fibrosis.