Purpose The goal of this study was to explore the outcomes of unilateral and bilateral approach percutaneous kyphoplasty (PKP) using CT-guidance in the treatment of severe osteoporotic single-level vertebral biconcave-shaped fracture. Methods We retrospectively reviewed 89 patients with severe osteoporotic single-level vertebral biconcave-shaped fracture who had undergone unilateral and bilateral PKP surgeries using CT-guidance at our hospital between June 2013 and June 2019, and followed for at least 1 year. All patients were divided into unilateral (the transverse process-pedicle approach, n = 49) and bilateral (the pedicle approach, n = 40) groups. We collected the clinical and radiological evaluation results during postoperative and last follow-up periods. Results Our findings revealed that the surgery time for the unilateral group was significantly shorter than that of the bilateral group at P < 0.05. The amount of bone cement and radiation exposure of the unilateral group were significantly lesser than that of the bilateral group ( P < 0.05). Relative to preoperative data, the values of the VAS score and Oswestry disability index (ODI) were significantly improved at 1 day after surgery and the last follow-up in the two groups ( P < 0.05). Notably, the median height of vertebra at 1 day after surgery and the last follow-up in the unilateral group was significantly restored than that of preoperative data ( P < 0.05). However, the median height of vertebra at the same time intervals in the bilateral group showed no significant change compared with preoperative data ( P > 0.05). Furthermore, the rate of bone cement leakage and incidence of adjacent-level vertebra fracture were not significantly different in the two groups (P > 0.05). Finally, both groups can obtain an asymmetrical distribution of bone cement in the vertebra. Conclusion Compared to the bilateral PKP, unilateral PKP using CT-guidance in the treatment of the sOVBFs exhibits significantly shorter operation time, lesser radiation dose, and complications. Moreover, unilateral PKP can restore the median height of the vertebral body and eventually obtain a symmetrical distribution of bone cement in the vertebra.