The reality star, who married her husband Eric Brown earlier this year, gave birth to Eric Bueno Brown Jr in the early hours of August 26, Us Weekly reports.
Preston's son weighed 8lb, 7oz when he was born in New York Hospital in Queens.
"Angelea, Eric and Eric, Jr are doing great," Preston's rep said. "Right now Angelea is on super mother mode, tending every minute to her beautiful newborn son! She's ecstatic and cries happy tears because she can't believe he's here."
Eric is the second child for Preston, who gave birth to a daughter, Giavonna Anchell, in 2003. However, Giavonna was born three months prematurely and passed away 23 days later.
Following Eric's birth, Preston's rep added: "She's been given another opportunity to be a mother. She is also ready to get back to work to see what challenges lie ahead being a mother, model and actress! The happy parents thank you for your warm wishes!"
Preston appeared in the 14th cycle of America's Next Top Model, where she made the final four. She also featured in last year's All-Stars cycle but was controversially disqualified during the season finale.