The visiting MK Dons, who had not scored this year away from home, suddenly found their shooting form to make sure that City's dismal home record continued. They have not won at Valley Parade since last October.
A two-goal salvo in the 56th and 58th minutes knocked the stuffing out of the Bantams as they looked to be back in it at 2-1.
The first came from midfielder Ben Harding, who cashed in when no-one bothered to challenge him on the edge of the box to rifle home a fierce shot.
Then Izale McLeod, who had netted in the first half, took advantage of some more home generosity by angling a shot into the far corner.
Even a triple substitution on 77 minutes by City boss Colin Todd could not turn the tide.
Bradford had looked well in control during the first half hour without really threatening the visitors' goal.
Nicky Summerbee skilfully slipped past a defender before lashing a low centre across goal, but there was no-one there to ram it into the net.
Then full-back Peter Atherton hit a great through ball to Dean Windass, but Bradford's leading scorer snatched at the chance and hit the ball way off target.
The home side still looked up for it and Craig Armstrong tried a 25-yard effort which went wide.
But the Dons, who have the worst away record in the division, suddenly found an extra gear and hit Bradford with a devastating double blow.
On 33 minutes Wade Small started a run from just over the halfway line and was unchallenged as he cut inside to fire home a 25-yard shot.
It may have been against the run of play, but what followed was not.
A minute before the interval McLeod unleashed a left-foot shot which left keeper Paul Henderson helpless.
Within two minutes of the restart Windass pulled one back when a goal-line clearance from a David Wetherall header hit the striker and went into the net.