Objective To analyze the genetic causes, imaging manifestations, and outcomes of fetal multicystic dysplastic kidney.Methods We retrospectively collected clinical data of 80 fetuses with multicystic dysplastic kidney admitted to our hospital from May 2017 to May 2023, and analyzed their genetic causes, imaging manifestations, and outcomes.Results Out of 80 fetuses with multicystic dysplastic kidney, 11 cases (13.75%) were detected with chromosomal abnormalities, including 1 case (1.25%) with numerical abnormalities and 10 cases (12.50%) with chromosomal copy number variation (CNV). Among the 80 fetuses with multicystic dysplastic kidney, there were 39 fetuses with left multicystic dysplastic kidney (48.75%), 37 fetuses with right multicystic dysplastic kidney (46.25%), and 4 fetuses with bilateral multicystic dysplastic kidney (5.00%). Sixty-four cases (80.00%) of the fetuses had abnormalities only in the urinary system, and 16 cases (20.00%) of the fetuses were complicated with abnormalities in other systems, among which those in the cardiovascular system (8 cases), the limb skeleton (3 cases) and the nervous system (3 cases) were the most common. The detection rates of the pathogenic CNV in fetuses with abnormalities only in the urinary system and those combined with abnormalities in other systems were 10.94% (7/64) and 12.50% (2/16), with no statistically significant difference (P > 0.05). Among fetuses with abnormalities only in the urinary system, the detection rates of the pathogenic CNV in fetuses with unilateral and bilateral multicystic dysplastic kidney were 9.84% (6/61) and 33.33% (1/3), with no statistically significant difference (P > 0.05). The follow-up on the 80 fetuses with multicystic dysplastic kidney found 8 cases lost to follow-up (10.00%), 31 cases of artificial termination of pregnancy (38.75%), none of intrauterine fetal death (0.00%), 41 cases of live birth (51.25%), and 1 case of neonatal death (1.25%).Conclusions Chromosomal microarray analysis may increase the detection rate of fetal multicystic dysplastic kidney. Imaging examination is of certain value in the diagnosis of multicystic dysplastic kidney, and provides a basis for prenatal diagnosis, genetic counseling and prognosis evaluation for fetal multicystic dysplastic kidney.