The clinical data, follow-up records and genetic results of a child with growth retardation and systemic multiple malformations, of whom was diagnosed Loeys Dietz syndrome (LDS), were retrospectively analyzed.This was a 3 years and 3 months old boy presented with incomplete cleft palate, spasm of middle fingers in both hands, hernia and hyperextension of knee joint.Color doppler ultrasound showed dilation of aortic sinus and ascending aorta, and mo-derate aortic regurgitation in the child.The analysis of genetic cardiovascular gene sequencing showed that there was a heterozygous mutation in TGFβR2 gene, which was a missense mutation.The child was diagnosed LDS type 2 according to the results of gene detection and clinical characteristics.He underwent " Bentall" aortic valve replacement + coronary artery lengthening transplantation (Cabrol) in Guangdong Provincial People′s Hospital.Postoperative recovery was satisfactory.This is the youngest case of Bentall operation reported in China.Connective tissue and organs are involved in the LDS.Systemic arteries, especially big arteries, are seriously involved and progressing rapidly.The combination of gene detection and clinical symptoms is the great value in the differential diagnosis of LDS.Echocardiography is an important method to monitor the progress of cardiovascular disease in children with LDS, which is important for the selection of surgical methods and timing.Bentall operation can also achieve good prognosis in children under 4 years old.