Despite significant progress in the prenatal diagnosis of congenital heart disease and the postnatal management, the prenatal evaluation of fetal heart function remains difficult. The unique characteristics of the fetal circulation have a significant impact on its cardiac function. Commonly used physiological concepts about the function of the heart can be misleading when applied to the intrauterine situation. Most noninvasive parameters of cardiac function are not validated in the fetus. In addition, unlike structural defects that can be easily confirmed after delivery, functional hemodynamic abnormalities diagnosed in utero cannot be verified postnatally with certainty as the neonatal circulation defers considerably from the fetal circulation. This review attempts to describe commonly used methods of assessment of fetal cardiac function, their physiological basis and, their utility in clinical practice.