The Arsenal midfielder's girlfriend Lauren Neal, 22, gave birth to a boy, Archie Jack.
Wilshere, who is not expected to play until February after ankle surgery, said on Twitter: "The proudest day of my life today!
"Archie Jack Wilshere was born at 15.06 uk time and weighed 7lb 11oz. I am the happiest man in the world!"
Archie is Jack and Lauren's first child and the pair were 'shocked but delighted' to find out she was pregnant a few months after they split up.
He split with Lauren, 22, who works as a hairdresser, at the start of this year but they rekindled their relationship this summer.