Objective: The purpose of this study was to compare the prenatal diagnostic capabilities of two-dimensional ultrasonography versus adjunctive three-dimensional ultrasonography for fetal cleft lip and palate. Study Design: Fetuses that were suspected of a facial cleft were then examined sequentially with two-dimensional ultrasonography then with a targeted scan of the fetal face with three-dimensional ultrasonography. The images were coded as cleft, no cleft, or equivocal for lip and palate. Postnatal outcome follow-up was obtained. Results: Fifty-three of 57 fetuses had outcome results available. The diagnostic accuracy (true positive + true negative) of adjunct three-dimensional ultrasonography versus two-dimensional ultrasonography alone were improved for cleft lip (100% [53/53 fetuses] vs 91% [48/53 fetuses], P < .05) and cleft palate (89% [47/53 fetuses] vs 57% [30/53 fetuses], P < .05) Conclusion: There is significant improvement in diagnostic accuracy with two-dimensional ultrasonography with adjunctive three-dimensional ultrasonography compared with two-dimensional ultrasonography alone for the prenatal evaluation of facial clefts. ( Am J Obstet Gynecol 2002;187:946–9.)