Objecytive Percutaneous endoscopic surgery via the interlaminar approach and transforaminal approach are commonly used for the treatment of degenerative lumbar spinal stenosis, and in order to compare the clinical efficacy of Percutaneous Endoscopic Large channel Translaminar approach (PEL-TL) and Percutaneous Endoscopy Conventional channels Transforaminal approach (PEC-TF) in the treatment of degenerative L4/5 spinal stenosis. Method A retrospective analysis was conducted on 124 patients who underwent percutaneous endoscopic single segment unilateral decompression surgery for degenerative L4/5 spinal stenosis in our hospital from January 2020 to January 2023. They were divided into PEL-TL group and PEC-TF group according to different surgical methods. Recording general information of two groups of patients, including age, gender, course of disease, and length of hospital stay. Recording the surgical time, C-arm fluoroscopy frequency, incidence and type of complications for two groups of patients. CT was used to measure the Lateral Recess Angle (LRA), and MRI was used to measure the Dural Sac Cross sectional Area (DSCA) to evaluate the degree of lateral recess stenosis and compare the neurological decompression between the two groups. Using the White Panjabi scoring system (WP) to evaluate local stability before and 3 months after surgery. Recording the Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) for preoperative and postoperative hip and lower limb pain in two groups of patients. Evaluateing the efficacy using the modified Macnab criteria one year after surgery. Results There was no statistically significant difference in general information between the two groups of patients (P > 0.05). The surgery time in the PEL-TL group was shorter than that in the PEC-TF group (P < 0.05). The number of C-arm fluoroscopy in the PEL-TL group was significantly lower than that in the PEC-TF group (P < 0.05). There was no statistically significant difference in the incidence of complications between the two groups of patients (11.1% in the PEL-TL group and 14.3% in the PEC-TF group) (P > 0.05). The postoperative recurrence rate of PEL-TL is lower than that of PEC-TF (P < 0.05). All enrolled patients were followed up regularly for 1 year. There was no significant difference in preoperative LRA and DSCA between the two groups of patients (P > 0.05). After 1 year of surgery, LRA and DSCA in both groups were significantly larger than before (P < 0.05). There was no statistically significant difference in postoperative DSCA between the two groups, but LRA in the PEL-TL group was more significantly larger than that in the PEC-TF group (P < 0.05). There was no statistically significant difference in preoperative and postoperative WP between the two groups of patients, and there was no significant difference in WP in two groups. The ODI scores and the VAS scores of buttock and lower limb pain at each follow-up time point after surgery in both groups of patients showed significant improvement compared to before surgery. There was no statistically significant difference in functional scores between the two groups at each follow-up time point (p > 0.05). One year after surgery, the efficacy was evaluated using the modified Macnab criteria. Among them, in the PEL-TL group, 36 cases were excellent and 14 cases were good, with an excellent and good rate of 92.6%. In the PEC-TF group, 48 cases were excellent and 16 cases were good, with an excellent and good rate of 91.4%. There was no statistically significant difference between the two groups (p > 0.05). Conclusion Both surgical methods can achieve satisfactory clinical efficacy in treating degenerative lumbar 4/5 spinal stenosis. PEL-TL has fewer C-arm fluoroscopy times, wider decompression range, shorter surgical time, and lower recurrence rate during surgery, while PEC-TF can be routinely performed under local anesthesia to reduce anesthesia risk.