Objectives:To compare the shon-term clinical effects of stand-alone oblique lateral interbody fu-sion(SA 0LIF)and posterior lumbar interbody fusion(PLIF)in the treatment of degree Ⅰ single-segment degen-erative lumbar spondylolisthesis.Methods:The data of 80 patients with degree Ⅰ single-segment degenerative lumbar spondylolisthesis who met with the inclusion criteria of this study between March 2019 and August 2021 were retrospectively analyzed.The patients were divided into the SA 0LIF group(38 cases)and PLIF group(42 cases).The intraoperative blood loss,operative time,postoperative drainage volume,postoperative am-bulation time,postoperative length of hospital stay,and complication rate were compared between the two groups of patients.The disc height(DH),foraminal height(FH),spondylolisthesis angle(SA),and fusion rate(FR)were measured before and after surgery and during follow-up.The visual analogue scale(VAS)and 0swestry disability index(ODI)were used to evaluate the short-term clinical efficacy.Results:The intraoperative blood loss(61.3±21.3mL vs 123.5±22.4mL),operative time(89.8±30.1min vs 112.1±15.2min),postoperative drainage volume(44.2±23.2mL vs 163.5±22.2mL),postoperative ambulation time(2.0±1.0d vs 4.2±2.1d),postoperative hos-pital stay(5.8±3.0d vs 9.2±5.3d),and complication rate(5.3％vs 19.1％)were all less in the SA OLIF group than those in the PLIF group(P＜0.05).At 1 week postoperatively,the ODI[(19.3±6.6)％vs(30.9±8.3)％]and lower back pain VAS scores(2.3±0.5 vs 3.0±1.0)of the SA OLIF group were lower than those in the PLIF group(P＜0.05),but no statistical difference was there between the two groups at 3 months after surgery and final follow-up(P＞0.05).During postoperative follow-up,the postoperative increases of DH and FH in the SA OLIF group were higher than those in the PLIF group(P＜0.05),and there was no significant difference in SA and FR after surgery between groups(P＞0.05).Conclusions:SA OLIF and PLIF are equally safe and effective in treating degree Ⅰ single-segment degenerative lumbar spondylolisthesis,However,SA OLIF has the advantages of less surgical trauma,faster recovery,and better opening effect on the intervertebral space.