The former X Factor star's publicist Max Clifford confirmed the news via Twitter earlier today.
He wrote: "Congratulations to our lovely client @5taceysolomon who gave birth to a baby boy earlier today, both baby and mum are doing well."
This is Solomon's first child with fiancé Aaron Barnham, to whom she became engaged in December after three years of dating.
Solomon was widely criticised recently after she was photographed smoking while seven months pregnant.
She has expressed fear that she will experience postnatal depression again after giving birth, as she did with her first son Zac.