OBJECTIVE: The measurement of liver size can be used for the diagnosis of the fetal growth abnormality (FGR, macrosomia etc.). The purpose of this study was to evaluate a mathematical relationship between the fetal liver size(liver length or volume) and the gestational age in the normal pregnancies. Brief comparisons were also tried on the base of the degree of the correlation between liver length and its volume. METHODS: We collected 54 singleton pregnancies of 20 to 36weeks of gestation for measuring fetal liver length and 57 singleton pregnancies for measuring fetal liver volume. We used Combison 530 utrasonic machine(Kreztechnik AG, Zipf, Austria). RESULTS: There was significant correlation between liver size( length and volume) and gestation age. And the liver volume better correlated with gestational age than liver length(r=0.93 : r=0.78, p<0.0001, p<0.0001). CONCLUSION: Ultrasonic measurement of fetal liver size is a reliable indicator of fetal growth, especially liver volume. Therefore these data may have a potential value for the prediction of abnormal fetal growth(FGR, macrosomia).