In April, a court ruled the defendant was a woman and issued an acquittal, saying only men could be convicted of penetrative sex with a minor.
But in a landmark judgment, the court of appeal overturned that ruling, saying the law was gender-neutral.
The defendant has now been sentenced to 10 years in jail.
Singaporean media have reported the case as the first time a woman has been convicted of the sexual abuse of a female child.
False identity
