Abstract: Objective To explore the application and accuracy of spatio-tem-poral image correlation(STIC)in prenatal diagnosis for cardiac malformations. Methods Fetal echocardiography was performed to screen fetal cardiac abnormalities,and STIC was followed for the suspicious fetus.The terminational or deathfetus underwent histopathological examination,while the live birth received neonatal ultrasound diagnosis.The diagnostic accuracy on cardiac malformations was compared between STIC and two-dimensional ultrasound. Results Total 12 782 cases were screened,217 cases were involved,and final valid cases were 203,in which 112 cases were diagnosed by autopsy pathology,91 cases by neonatal ultrasound or CT,MRI.The diagnostic accuracy of ultrasonic cardiogram on fetal cardiac malformations was 94.09%,missed diagnosis rate was 4.43%,and misdiagnosis was 1.48%;the diagnostic accuracy of STIC was 98.52%,missed diagnosis rate was 0.99%,and misdiagnosis rate was 0.49%.The diagnostic accuracy STIC was higher than that of ultrasonic cardiogram(χ²=5.61,P＜0.05),but the missed diagnosis rate was lower(χ²=4.58,P＜0.05),yet there was no statistical difference on misdiagnosis rate between two measures(χ²=0.25,P＞0.05). Conclusion Real-time 4D STIC has better clinical application value on auxiliary diagnosis in fetus with cardiac malformations,and it is not only beneficial to remedy the defects of two-dimensional ultrasound,but also can improve the accuracy on the auxiliary diagnosis of fetal cardiac malformations,so provides more reliable and scientific basis for prenatal screening.