Objective To investigate the early efficacy and advantages of expansive intra-canal plasty (EICP) in the treatment of central lumbar spinal stenosis in the elderly. Methods A retrospective analysis was performed on 23 elderly patients with central lumbar spinal stenosis due to degeneration and with main manifestation of intermittent claudication admitted in our hospital from January to July 2015. They were all treated with EICP. The operation time, blood loss, intraoperative monitoring of spinal nerve, postoperative drainage, postoperative complications, postoperative images of lumbar spinal fusion of the lumbar spine and the cross-sectional area during follow-up, Japanese Orthopaedic Association (JOA) score, Oswestry disability index (ODI), improvement of intermittent claudication were observed and recorded to evaluate clinical outcomes. Results All cases were followed up for 12 to 16(13.8±1.5) months. The average bleeding amount of single segment was (257.5±47.1)ml, the operation time (114.5±16.8)min, and postoperative drainage amount (150.0±37.6)ml. For double segments, the intraoperative blood loss was (344.5±55.6)ml, the operation time was (161.8±161.8)min, the postoperative drainage amount was (225.4±40.1)ml, and no abnormality was found in intraoperative spinal cord monitoring. There were 3 patients having postoperative complications. One case had dural sac tear, and the postoperative cerebrospinal fluid was stopped in 5 d after symptomatic treatment. Two cases had postoperative delayed healing of incision, and the incisions were healed well after 3 weeks’ active treatment. CT scanning showed that the cross-sectional area of narrowed space was significantly increased from preoperative (73.32±2.67)mm² to (213.33±3.26)mm² in 1 week postoperatively in L3-4 segments, and from (116.24±2.17) to (260.16±3.67)mm² in L4-5 segments (P<0.05). In 1 year after operation, the JOA score, ODI score and intermittent claudication were obviously improved (P<0.05). According to JOA score, the postoperative improvement rate was 90.05%. The fusion rate was 78.2%, 86.9% and 95.6%, respectively in 3 and 6 months, and 1 year postoperatively. Conclusion EICP is an innovation for the traditional resection of whole lamina and decompression in the treatment of central lumbar spinal stenosis, reflecting the concept of modern surgery, precise surgery and minimally invasive surgery. It can not only exert effective decompression in the narrow canal, but also protect the native structure behind the lumbar spine, maintain the stability of lumbar spine, increase the bone graft area, and elevate the rate of fusion. It exerts effective surgical efficiency and causes low incidence of complications, and is an effective approach for lumbar spinal stenosis.