Leeds (16) 28
Tries: Tansey, Burgess, Scruton, Ablett, McGuire Goals: Sinfield (3), Burrow
Bradford (12) 18
Tries: Sykes, Evans, Godwin Goals: Harris (3)
Jamie Peacock tries to get through Terry Newton's efforts
Leeds withstood a strong display from Bradford to claim a fourth win of the season over their Yorkshire rivals.
After going behind to an early Paul Sykes try, Leeds hit back with scores from Jordan Tansey, Luke Burgess and Nick Scruton.
Tries either side of the break from James Evans and Wayne Godwin gave the Bulls a narrow advantage.
But Carl Ablett restored the lead for the Rhinos on the hour before Danny McGuire's late try made it safe.
The Rhinos were dealt an early blow when winger Scott Donald was forced off with a rib injury after a clash with Michael Platt.
In the resulting scuffle, Platt and Leeds' Rob Burrow were both sent to the sin-bin.
Moments later, the Bulls showed greater composure when half-back Ben Jeffries made a superb darting run and his inside pass found Sykes who touched down with Iestyn Harris adding the extras.
But the Rhinos, who have struggled for form recently with five defeats in their last eight outings, got themselves back into the game.
Tansey took a long offload from Brent Webb to go over but Sinfield missed, although he was successful five minutes later when Matt Diskin broke through and the supporting Burgess was on hand to go over for a try.
Then England captain Jamie Peacock offloaded to send Scruton over the line from close range.
Evans rose highest to go over in the left-hand corner just before the break and Harris converted again.
Full of confidence, the Bulls made a better start to the second half and Evans turned provider, palming the ball back for Godwin to ground under the posts.
Leeds refused to give in and Tansey went over for a second time but his effort was disallowed by the video referee.
But Ablett was the quickest to a clever kick from Diskin with 20 minutes left and Burrow added the extras to give his side a 22-18 advantage.
Bradford tried to rally but in the final minute McGuire went over from close range and Sinfield once again added the extras.
Leeds coach Brian McClennan on the injury to winger Scott Donald:
"He's popped a rib cartilage, but we'll have to wait and see how long he will be out for.
"These injuries normally keep you out for three weeks and they're really uncomfortable.
"It's difficult to breathe, and he will be very sore."
Bradford coach Steve McNamara:
"I've been encouraged by these guys for a long, long time. I'm sick and tired of people talking about Bradford's demise.
"We're in a different stage as an organisation and as a team, and at this moment in time we are rebuilding the team and the organisation.
"With some of the issues and problems we've had, it's a massive effort to even be in there fighting for the six - never mind anything else."
Leeds: Webb, Smith, Ablett, Senior, Donald, McGuire, Burrow, Peacock, Diskin, Leuluai, Kirke, Ellis, Sinfield.
Replacements: Scruton, Burgess, Tansey, Worrall.
Bradford: Platt, Halley, Sykes, Evans, Tadulala, Jeffries, Harris, Vagana, Newton, Lynch, Cook, Finnigan, Langley.
Replacements: Johnson, Nero, Godwin, Kopczak.
Referee: B Thaler (Wakefield)