We report a 13-year-old girl with Loeys-Dietz syndrome (LDS) caused by a known transforming growth factor beta receptor II (TGFBR2) gene mutation, who developed aortic root dilatation and saccular aneurysm of the internal carotid artery. LDS is a rare, autosomal dominant aortic aneurysm syndrome with multisystem involvement. The disease is typically characterized by the triad of arterial tortuosity and aneurysms, hypertelorism, and bifid uvula/cleft palate. The characteristic LDS symptoms observed in the reported case included craniofacial dysmorphism (hypertelorism, cleft palate, blue sclerae, malar hypoplasia, retrognathia), skeletal deformities (scoliosis, talipes equinovarus, pectus deformity, arachnodactyly), congenital heart defects (patent ductus arteriosus, PDA), and arterial tortuosity and aneurysms. Molecular genetic testing revealed a heterozygous mutation (c.1610 G>C, p.R528C) in the serine-threonine kinase domain of the TGFBR2 gene. Magnetic resonance (MR) angiography showed aortic dilatation, tortuosity of bilateral supraaortic arteries, and saccular aneurysm on the right cervical internal carotid artery. LDS resembles Marfan-related disorders (Marfan, Shprintzen-Goldberg and vascular Ehlers-Danlos syndrome), but arterial tortuosity and aneurysms are characteristic for LDS, so a timely diagnosis of LDS is important for early diagnosis and intervention of aneurysms to prevent vascular events. Here, we describe a LDS patient who presented with arterial tortuosity and saccular aneurysm.