The model and businesswoman posted a sweet image to her YouGossip channel page on Tuesday afternoon (5 August), one day after her representative confirmed she'd given birth.
Katie gave no indication of the tot's name, simply saying: "Daddy's little girl."
'Daddy' was a reference to Katie's estranged husband Kieran Hayler. The baby's teeny tiny hand is seen clutching onto Kieran's finger in the intimate black and white picture.
Katie's rep confirmed on Monday night that Baby Price-Hayler had arrived two weeks early.
In a short statement posted to Twitter, the spokesperson said: "[We] can confirm that our client @MissKatiePrice has given birth to a baby girl this afternoon - no more details will be given at present."
We don't know yet whether Kieran was present at the birth but reports ahead of the big day had suggested Katie was eager for him to be at her bedside.
This pregnancy has been bittersweet for Katie.
Just days after announcing she was pregnant, she discovered that husband Kieran had been cheating on her with her best friend Jane Pountney.
Katie immediately vowed to divorce him but in recent weeks has indicated she is willing to work through their issues for the sake of their family.
The couple are also parents to baby son Jett, born last year.
Katie has three other children - Harvey, Junior and Princess - from previous relationships.
The baby's birth meant that Katie was (understandably) absent from her weekly Fubar Radio slot today, but co-host Mark Dolan made sure to give the new mum a shout-out on air.
In a special message, Mark told listeners who had tuned in: "I would like to wish Katie Price, my fabulous co-host, our very best wishes for arrival of a brand new little girl. We're delighted. It's the dawn of a new era. This is just what the world needs, a little Katie Price running around causing havoc at nursery. Well done, you've done it again!"
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