ObjectiveTo report a simple and safe method for in situ fenestration of left subclavian artery in thoracic endovascular aortic repair (TEVAR).MethodsTwenty-eight patients received in situ fenestration of left subclavian artery in TEVAR from June 2018 to May 2019 in our center, including 23 males and 5 females at an average age of 57.7±9.6 years. Among them, 12 patients used adjustable sheath or guiding catheter (a group A) and 16 patients used "J. D"technique (a group B). The clinical efficacy of the two groups was compared.ResultsIn the group A, 1 patient failed to receive fenestration and was transferred to the chimney technique. In the group B, 1 patient due to the traction system shift during operation, was completed by traditional adjustable sheath puncture. The group B had shorter alignment-perforation time and trigger time and less complications. There was no significant difference in endoleak during short-term follow-up between the two groups.ConclusionThe "J. D" technique is simple, safe and easy to obtain materials. It effectively reduces the risk caused by difficult sheath alignment during the in situ fenestration of the left subclavian artery. Although the results of recent follow-up are not significantly different from traditional methods, it still needs to accumulate the cases to observe the possible risks and difficulties.