Flying winger Dylan Mottley-Henry, central defender James King, attacker Joe Brennan and midfielder Sam Wright, who was named Youth Team Player of the Year, have all been awarded pro deals with the club.
The foursome all featured this season for City's Under 18s, who successfully defended their Football League Youth Alliance North East Division title.
As well as being named on the bench for Parkinson's side on a number of occasions, Mottley-Henry actually made his senior debut for City last month, coming on as a second half substitute during the Easter Monday fixture against Preston North End at the Coral Windows Stadium.
King and Wright have featured on the bench for City as well this campaign.
King and his team-mate Brennan have enjoyed a taste of senior football themselves this season thanks to loan periods at Whitby Town and Ossett Town respectively.
Young striker Reece Webb-Foster will continue with the youth team next season as a second year apprentice.
Webb-Foster became the second youngest player ever to play for City when he came on as a late substitute in the Bantams' Capital One Cup third round tie at Milton Keynes Dons earlier this season.
Parkinson said: "Taking on four of our scholars as professionals is a good sign in terms of the standards we have here at our academy.
"It is also a good message to the rest of the kids in our youth system that there is the opportunity to get a pro contract."