Objective Aims Discuss thevalue about three-dimensional spoiled gradient echo (3D GRE) sequence in the diagnosis of knee joint cartilage injury by observing and analyzing the signal strength of cartilage and the change of the thickness and shape, etc., to provide diagnostic basis for early detection of articular cartilage injury. Methods Collect 150 patients' cases of knee MRI imaging data between18 to 60, divided into two groups 18 to 40 and 41 to 60 years old. Conventional T1WI, T2WI, T2WI FS and three-dimensional spoiled gradient echo imaging (3D GRE) sequence MRI imaging, on knee joint cartilage and on sagittal MRI 3D GRE sequence a knee inside and outside joints under the surface and patellar cartilage is the most thick place, a total of 5 articular cartilage thickness, applying SPSS 19.0 statistical software for statistical analysis with P<0.05 for the difference statistically significant. Results in the inspection of knee joint cartilage lesions, the three-dimensional spoiled gradient echo(3D GRE) sequence image display the cartilage's signal strength, thickness and the clearest shape change, and the highest organization of the image resolution. Conclusion MRI three-dimensional spoiled gradient echo(3D GRE) sequence technique is currently the best in knee joint cartilage lesions, the more serious cartilage damage is, the thinner thickness of cartilage is, and can reduce missed diagnosis and misdiagnosis.