Objective This study aimed to describe the extended intradural anterior transpetrous approach (ATPA) and its usefulness for the surgical resection of petroclival meningiomas (PCMs) of the cerebellopontine angle (CPA) and/or diaphragma sellae (DS) extension. Methods Between January 2017 and December 2019, a total of 22 patients with PCMs extending to the CPA/or DS underwent surgery via extended intradural ATPA by the senior author (Xr.X.). We retrospectively analysed the clinical data, radiological findings, surgical treatment, complications, and outcomes of patients and discussed the operative technique. Results In 22 patients, the tumours were gross totally removed (Simpson I and II) in 18 patients (81.8%), subtotally (Simpson III) in 3 patients (13.6%), and partially (Simpson IV) in 1 patient (4.5%). One patient died 48 days after the operation, and no recurrence was found in 21 patients during a median follow-up of 26 months. Postoperative complications included in abducens nerve palsy in 12 patients with recovery in 10 patients, facial numbness in 4 patients with recovery in 3 patients, and hemiplegia and oculomotor nerve palsy in 1 patient each with recovery in all patients. The postoperative MRI showed temporal lobe oedema but no clinical symptoms in 3 patients. Conclusion Extended intradural ATPA is an alternative approach for PCMs of the CPA and/or DS extension. The single approach can expose both the sellar region and the posterolateral area of the IAC, which is advantageous for extended intradural ATPA.