Abstract: Objective To investigate the clinical value of systematic ultrasonography combined with three-dimensional surface imaging in the diagnosis of fetal external ear malformation.Methods A total of 5760 pregnant women accepted system prenatal examination from January 2016 to January 2017 in our hospital was recruited as the research objects. The technology of system ultrasound combined with 3 D surface imaging ultrasound was used for all of the cases. The relationships among the frequency of ultrasonic examination, the rate of external ear display and the detection rate and missed diagnosis rate of fetal external ear were evaluated.Results Compared with the first external ear display rate, the second display rate was higher (P<0.05). The diagnosis rate of fetal external ear malformation was 75.00%. The missed diagnosis rate was 25.00%.Conclusion The technology of system ultrasound combined with 3 D surface imaging ultrasound used to diagnose fetal external ear malformation has great practical value. It can effectively improve the correct rate of diagnosing fetal malformation outer ear.