Objective To analyze the risk factors and CT imaging features of lumbar disc herniation. Methods 50 cases of patients with lumbar disc herniation confirmed by operation and pathology were selected as the observation group and another 50 cases of healthy controls were selected as the control group at the same time. According to the self-designed epidemiological questionnaires, the risk factors of lumbar disc herniation were analyzed and summarized and the CT imaging features of lumbar disc herniation of different degrees were also analyzed. Results Multiple and Logistic regression analysis showed that body mass index, continuous sitting time, waist injury history and bending degree were the independent risk factors of lumbar disc herniation. The protrusions in mild patients were with curved edges which were smooth. The nucleus pulposus prolapsed or protruded. The nucleus pulposus herniation density mainly was equal to or less than 80. The protruding area of zone 1 horizontal plane was large and the nerve root mainly was clinging. Moderate and severe patients were with hill-shaped margins which were irregular. The nucleus pulposus mainly prolapsed. The density of nucleus pulposus herniation mainly was more than 100. The protruding area of zone 3 horizontal plane was large and nerve root was compressed, clinging or adhesive. Conclusion Body mass index, continuous sitting time, waist injury history and bending degree were the independent risk factors of lumbar disc herniation. There are significant differences in CT imaging features between different severity of lumbar disc herniation.