Endotension is an unpredictable late complication of endovascular aortic aneurysm repair (EVAR). This case report will discuss the successful treatment of enlarged aneurysmal sac due to endotension using the relining technique. An 81-year-old male complained of nondecreasing huge aneurysm sac. He had undergone EVAR for infrarenal abdominal aortic aneurysm 7 years prior and no endoleak was found through follow-up. Initially computed tomography-guided sac aspiration was tried, but in vain, Relining using the double barrel technique and tubular endograft for modular diconnection, which was unexpectedly found in the original endograft, were performed sucessfully. During follow-up after the relining procedure, the size of aneurysm sac continued to decrease in size. The relining technique is effective mothod for treating endotension.