Intracranial mycotic aneurysm (MA), also known as intracranial infectious aneurysm, is a rare type of intracranial aneurysm. However, it carries a high mortality rate of 80% when ruptured and 30% even when unruptured. Here we report a 22-year-old male patient who consecutively developed two ruptured intracranial MAs related to infective endocarditis. The time interval between the two attacks was approximately seven months. The second aneurysm formed and ruptured regardless of long-term antibiotic therapy and cardiac surgery to replace the dysfunctional aortic valve. This case indicates that intracranial MAs may develop even after successful treatment of the underlying cardiac disorders, and hence close angiographic follow-ups may be warranted following the cardiac surgery.