Background and Aims In recent years, the authors' hospital used the in-situ needle fenestration to preserve the left subclavian artery (LSA) in thoracic endovascular aortic repair (TEVAR) for the treatment of thoracic aortic diseases, which achieved satisfactory clinical results. This study was performed the safety and effectiveness of the application of this method through summarizing the relevant data.Methods The clinical data of 25 patients with thoracic aortic diseases undergoing TEVAR with in-situ needle fenestration for LSA revascularization from February 2017 to December 2019 were retrospectively analyzed. There were 22 males (88%) and 3 females (12%), aged 45-68 years, with an average of (62.1 ± 11.2) years.Results Of the 25 patients, technical success was achieved in 24 cases (96%). All patients had no major perioperative adverse events within 30 d. All patients were followed up for 6-31 months and the median follow-up time was 13 months. All type II, III and IV endoleak disappeared at the median follow-up of 13 months. During the follow-up period, the main stent and branch stents were in good shape without obvious stenosis or displacement.Conclusion TEVAR with in-situ needle fenestration for LSA preservation in the treatment of thoracic aortic diseases is feasible and effective, and the short-term follow-up is satisfactory.