BJECTIVE: To discuss the clinical effect and the application of AF device fixation system and PROSPACE interbody fusion cage on treating lumbar spondylolisthesis. METHODS: Twenty-one cases of lumbar spondylolisthesis treated by operation from 1999 to 2002 were analyzed retrospectively (13 males and 8 females, 25-66 years old averaging 42 years). We had thorough decompression on the part of nerve compression and had replacement and fixation of the slippage vertebral body with the AF transpedicular screw/rod system so that the normal spine physiological curvature could be recovered, and then performed the posterolateral interbody fusion with implanting the PROSPACE filled with autograft bones. RESULTS: All the patients were followed up for 3 months to 3 years with an average of 15 months. The preoperation symptoms improved in 20 cases (95.2%). CONCLUSION: The combination of AF device fixation system and PROSPACE interbody fusion cage can relieve effectively nerve compression, recover the normal spinal physiological curvature, maintain the height of interbody and promote the nerve fusion. It is reliable and effective in the treatment of spondylolisthesis.