Abstract: Objective To investigate the difference in sagittal spine-pelvic parameters between lumbar degenerative and isthmic spondylolisthesis patients.Methods A total of 80 patients who were admitted to Xuzhou Central Hospital from September 2020 to November 2021 were enrolled, including 37 degenerative spondylolisthesis cases (a degeneration group) and 43 isthmic spondylolisthesis cases (an isthmi group). Meanwhile, 48 healthy volunteers without related symptoms during physical examination were selected and set a normal group. The following spinal and pelvic parameters were measured on lateral radiographs of the full length of the spine in the standing position:pelvic incidence angle (PI), lumbosacral inclination angle (SS), pelvic inclination angle (PT), lumbar lordosis angle (LL), thoracic kyphosis angle (TK), sagittal vertical axis (SVA), slip angle (SA), slippage distance (SD) and slip percentage (SP). The three groups were compared for the parameters mentioned above, while the correlations between SP and the spine-pelvis parameters were analyzed.Results The isthmi group showed remarkably higher PI, PT, LL, and TK than the normal group (P<0.05). The degeneration group presented significant increases in PI, PT, and SVA, as well as decreases in LL, compared with the normal group (P<0.05). The isthmi group showed remarkably higher LL, SA, and TK, as well as lower SVA than the degeneration group (P<0.05). For the degeneration group, SP was significantly correlated with PI, PT, SVA, and SD. For the isthmi group, SP was significantly correlated with PI, LL, and SD.Conclusions Higher PI may be a predisposing factor for degenerative and isthmic spondylolisthesis. PT is one of the predictive factors for degenerative spondylolisthesis, whereas LL is one of the predictive factors for isthmic spondylolisthesis.