The star's representative released a statement to People, confirming that Karolína was now the proud mum to a "healthy, beautiful baby boy." The name and date of birth of the newborn was not given.
Karolína, 31, and her husband Archie already share a six-year-old son, Tobin Jack.
Karolina Kurkova is already the proud mum to six-year-old Tobin
The Czech beauty has not yet announced her baby news on social media, but on Wednesday Karolína did take time to reflect on her former "Angel" days.
The statuesque blonde shared a picture on Instagram wearing a set of pale-blue wings and captioned it, "Fly #angels #fly", while tagging her close model friends including Adriana Lima, Alessandra Ambrosio and Lily Aldridge.
Her snap was uploaded just a day after the glitzy Victoria's Secret Fashion show.
The 31-year-old is best known for her Victoria's Secret modelling days
Karolína announced that she was pregnant with her second baby in July. The supermodel took to Twitter to share her joyous news, posting a picture of her son adorably kissing her growing bump.
"My second bundle of joy is on its way and Tobin can't wait! #Happiness #Love #KKBaby2," she wrote.
Tobin was born in October 2009, just a few months after Karolina and Archie married in secret. The couple got engaged earlier that summer while on holiday in Cape Town, South Africa.
On motherhood, Karolina said: "You become this powerful big mama who can deal with anything"
Shortly after her first son was born, Karolina opened up about motherhood in an interview with Access Hollywood. "I feel very different," she said. "After having a baby things just changed."
"Something inside of you switches and you become this powerful big mama who can deal with anything and do everything. I never sit down. I'm always running around. I'm sure other mothers feel the same way. I take care of the house, I cook, I work and I walk the runway."