Aim: To compare the outcomes of minimally invasive surgery (MIS) for degenerative spondylolisthesis transforaminal lumbar interbody fusion (TLIF) and oblique lumbar interbody fusion (OLIF). Materials & methods: The clinical and surgical characteristics and outcomes of 38 patients with MIS–OLIF and 55 with MIS–TLIF were retrospectively evaluated. Results: Procedures and hospital stay were shorter and blood loss was less, with MIS–OLIF than with MIS–OLIF. The clinical and radiographic outcomes were similar. Postoperative changes in disk height and foraminal dimension were greater and patient satisfaction was better with MIS–OLIF than with MIS–TLIF. Conclusion: The clinical findings associated with the two procedures were similar; but patients preferred MIS–OLIF, which is less invasive, to MIS–TLIF. Clinical trial registration number: ChiCTR1800019443.