Abstract: Objective To probe into the values of four dimensional ultrasound space-time correlation imaging (STIC) technical assistance in screening of fetal heart malformation.Methods A total of 120 cases of pregnant women whose fetuses were suspected congenital heart disease were selected as the research objects. All of them were screened by two-dimensional ultrasound technique and four dimensional ultrasound STIC technique. The collection data were analyzed offline. The pathological results were regarded as the gold standard for the dead fetus. The ultrasonic diagnosis results of newborn were regarded as the gold standard for the living fetus. The diagnostic results of two-dimensional ultrasound and four dimensional ultrasound STIC were observed.Results Among the 120 cases of fetus, 81 cases after induced labor were diagnosed as cardiac malformation by pathological examination. Among the other 39 living birth fetus, 38 cases were diagnosed as cardiac malformation by ultrasound. Among the 111 cases that were diagnosed by prenatal twodimensional ultrasound as fetal heart malformation, 103 cases were confirmed by the postpartum gold standard. Among the 9 cases that were diagnosed by two-dimensional prenatal ultrasound as normal, 1 case was confirmed by the postpartum gold standard. Among 119 cases that were diagnosed as fetal heart malformation by prenatal two-dimensional ultrasound combined with four dimensional ultrasound STIC, 118 cases were confirmed by the postpartum gold standard. And, 1 case that was diagnosed as normal by combination technique was confirmed by the postpartum gold standard. The diagnostic accuracy and the sensitivity of the two-dimensional ultrasound was 86.67% and 86.55%, respectively. The diagnostic accuracy and the sensitivity of the two dimensional ultrasound combined with four dimensional ultrasound STIC was 99.17% and 99.16%, respectively. The difference in the sensitivity and the accuracy between the two groups was statistically significant (P< 0.05). There was no significant difference in the specificity between the two groups (P>0.05).Conclusion The two-dimensional ultrasound combined with four dimensional ultrasound STIC can improve the diagnostic accuracy for suspected fetal heart malformation.