The Bantams went behind in the 42nd minute when Brentford's leading scorer Clayton Donaldson gave the visitors the lead against his home town club after a moment of misfortune by debutant defender Curtis Good.
Paul Hayes and Adam Forshaw were involved in the build-up down the right and, when the Australian-born youngster - on loan from Newcastle United - made a challenge, the ball ran free to Donaldson, who fired low into the far corner of the net to give the away side a 1-0 half-time lead.
Bradford manager Phil Parkinson made three substitutions in the 60th minute, bringing on leading scorer Nahki Wells, Gary Jones and Will Atkinson and they put new life into the home side, who scored a deserved equaliser after 70 minutes.
The Bees' defence failed to clear Atkinson's cross and when debutant Blair Turgott, on loan from West Ham, saw his shot rebound from a defender, James Hanson fired in the rebound from 10 yards.
Then, Wells almost won the match for the Bantams 10 minutes later but he was denied by the post.