Objective：This study aims to investigate the effect of three-dimensional computed tomographic angiograph（3D-CTA）virtual imaging guided the preoperative planning in microsurgical clipping of intracranial aneurysm（IA）. Methods：The clinical data of 198 patients with IA who underwent microsurgical clipping were retrospectively analyzed. All patients received 3D-CTA virtual imaging guided the preoperative planning for the surgical approach，bone window position and size，and compared with three-dimensional digital silhouette angiography（3D-DSA）. The short-term efficacy was evaluated by Glasgow Outcome Scale（GOS），incidence of postoperative chronic subdural hematoma（CSDH） was counted. Results：There were total of 223 aneurysms in 198 patients. 220 aneurysms were found by 3D-CTA，and 3 traffic aneurysms were missed，the coincidence rate with intraoperative detection was 99.55%，and the coincidence rate with 3D-DSA results was 98.65%. Total 192 patients were surgically clamped according to the preoperative planning，and the preoperative 3D-CTA imaging was basically consistent with the intraoperative findings，6 patients（3.03%）were not scheduled for surgery with large intracranial hematoma. The postoperative good prognosis rate was 69.19%，the mortality rate was 4.55%，and the incidence of CSDH was 5.29% during follow-up. Logistic regression analysis showed that the unruptured IA（UIA），subarachnoid hemorrhage（SAH）2~3 grade，CT value of lesions ≥40 HU，the subdural fluid collection（SDFC）diameter ≥5 mm and the SDFC volume ≥15 mL at 7 th day after surgery were independent risk factors for postoperative CSDH（P < 0.05）. Conclusion：3D-CTA imaging can obtain stereoscopic 3D model imaging，which can assist in the positioning of aneurysms and adjacent anatomical relationships，reduce the damage during clipping surgery and may reduce the risk of postoperative CSDH.