Fetal gallbladder duplication is a rare congenital malformation. In the literature only a few cases of fetal gallbladder duplication in utero is reported. A 22-year-old woman was referred to this hospital at 26 weeks of gestation for a routine ultrasound examination. A fetal duplication of gallbladder accompanied was diagnosed with ultrasonography (axial section of fetal abdomen on sonography showed two hypoechoic cyst-like structures). The diagnosis of duplication of gallbladder, was also confirmed with MRI. The result of cordocentesis was reported as 46, XY, t(X;10) (p11.2;q24.3) . Antenatal/natal/postnatal care was unremarkable. A novel chromosomal mutation (46, XX, t(X;10) (p11.2;q24.3) ) with duplicated fetal gallbladder which has not been reported previously was described.