The 37-year-old entrepreneur, who became a mother again through surrogacy on January 15, announced the news on her official website.
"Kanye and I are happy to announce the arrival of our healthy, beautiful baby girl. We are incredibly grateful to our surrogate who made our dreams come true with the greatest gift one could give and to our wonderful doctors and nurses for their special care," Kardashian wrote.
The "Keeping Up With The Kardashians" star said her two older children - North, four and Saint, two are excited top have a new member in the family.
The name of the newborn daughter is yet to be revealed.
According to TMZ, the couple went with surrogacy as a third pregnancy was risky for Kardashian as she suffered from placenta accreta, a serious condition during her second pregnancy.
They were believed to have hired the woman for USD 45,000 through an agency.