The reality star gave birth to her second child, a daughter, at LA's Cedars-Sinai Medical Centre on Sunday (July 8), E! News reports.
"Scott and I are overjoyed to welcome our precious angel Penelope Scotland Disick into our lives. We are forever blessed.
"Mommy and baby are resting comfortably," the couple said in a statement.
Kardashian had a natural birth, and Penelope weighed in at 7lb 14oz.
Kris Jenner confirmed that her daughter had an "easy delivery", describing her new granddaughter as "so cute".
"She looks just like [brother] Mason. She's so beautiful. We are so happy," Jenner added.
Kardashian and Disick welcomed Mason in December 2009.