Fetal duplicate kidney means that the fetus has malformation of the urinary system and abnormalities of the kidneys. Duplicate kidney is a common congenital anomaly, which can be manifested as renal pelvis malformation, ureteral malformation and so on. Fetal duplicated kidney may be caused by genetic or chromosomal abnormalities, or it may be caused by medication or disease, or exposure to harmful substances during early pregnancy. Fetal duplicate kidney requires detailed examination of genes and chromosomes to find out the cause of the disease. Based on the comprehensive examination results, we will make a judgment to clarify whether it is necessary to terminate the pregnancy early or wait for the birth of the child to undergo surgical treatment. If it is confirmed that the fetus is a duplicate kidney, it is recommended to consult the urology department of a provincial tertiary-level hospital to take a professional approach to solve the problem.