Objective　To investigate the clinical efficacy and valuation of myelography CT (CTM) in the surgical treatment of the senile multiple segmental lumbar spinal stenosis.　Methods　From March, 2009 to  July, 2011, there were 68 cases of multi-segmental degenerative lumbar spinal stenosis insenile patients who underwent posterior disc limited endoscopic decompression laminectomy or semi decompressive laminectomy surgery. All patients underwent CTM to confirm affected segments. VAS, JOA and ODI score were used to evaluate the efficacy of postoperative follow-up. 　Results　Unilateral single segments and bilateral single segments in CTM were significantly more than the number of segments liability section in MRI examination (P<0.01). The detection of bilateral double segments, three-segment and above unilateral, bilateral sections of three segments were significantly less than liability section MRI examination (P<0.01). Until March 2013, 63 patients were effectively followed up. Back and lower extremity VAS and ODI in 1 month after the surgery were significantly decreased (P<0.01), JOA was significantly increased (P<0.01). But no significant difference was detected in comparison between last follow-up and 1 month after the surgery. Efficacy was assessed by calculating the rate of JOA improvement in last follow-up, and the total efficiency was 96.83%.　Conclusion　CTM combined with limited liability segmental decompression is an effective way to treat elderly multi-segmental lumbar spinal stenosis, and its efficiency is significant. It can achieve an effective precise decompressionso that the surgeric trauma and impact to spinal stability can be minimized