The ex-minister expressed his excitement at the arrival of the baby in a tweet on Saturday.
Mr Fani-Kayode shared a photo of the baby but cropped out the face of the person carrying the baby.
“Welcome to the world son! You are a great blessing. I am so happy and so proud of you. God bless and keep you now and always. You shall fulfill your purpose and achieve destiny,” he wrote.
This is coming months after Fani-Kayode’s union with a model Precious Chikwendu collapsed. They have four children together.
The former minister has since then hosted several women in his home.
Unconfirmed reports say he has been spotted with a Lebanese-Nigerian woman Lilian Ellas, although the nature of their relationship remains unclear.