Derby, despite brave effort throughout, could not keep England's latest skipper quiet and he grabbed an early goal by twisting into the box.
Then in the final seconds made up for a catalogue of misses to sprint away and round Andy Oakes to squeeze home his 26th goal of the season.
Derby had arrived at Anfield knowing only victory would save them from the drop and with Blackburn winning anyway, the Midlanders' efforts would have gone to waste.
That they did not cave in against a side winning its seventh league game on the trot is all credit to them.
But they did not have enough up front to really trouble Liverpool despite the fact that the lack of a second for the home side left the game dangling until Owen's final effort.
With Manchester United winning so convincingly at Chelsea at lunchtime, Liverpool knew they would have to just keep on winning themselves to maintain their challenge.
It was rarely pretty, but it's 11 wins from their last 12 league games now and clearly no-one at Anfield is giving an inch.
It's now up to Arsenal now to beat Ipswich tomorrow to reclaim top spot for themselves in a wonderful title race that is going right to the death.
Liverpool just had to thank Owen. He scored a marvellous goal at Sunderland last week, got England's first on Wednesday and today grabbed the pair to see Derby's five-season stay in the top flight ended.
It's hard to keep Owen out of the limelight at the moment, even if he couldn't manage to even get into the top five of the sports writers' Footballer of the Year award announced earlier in the day.
His goals per game, despite the injuries, is still outstanding and England would not be in the World Cup Finals without his hat-trick in Germany.
But after receiving his European Footballer of the Year trophy before the match, he was clearly intent on continuing a magical week that had seen him become England's second-youngster skipper while grabbing another international goal in the rout of Paraguay.
Derby, with valiant, defiant fans giving them plenty of support, showed spirit and at least defensive ability but the pace and guile of Owen worried them.
Boss Gerard Houllier had preferred to leave Emile Heskey on the bench after injury kept him out of the England game and pair Owen with Nicolas Anelka, regardless of any perceived problems in the negotiations over his permanent move to Anfield.
Liverpool started with flowing style. Vladimir Smicer's astute pass forced Oakes to pluck the ball from the feet of Danny Murphy and Anelka.
Only a hooked volley from Branko Strupar, held by Jerzy Dudek following a cross from Giorgi Kinkladze gave Derby any hope of breaching Liverpool's defence.
The probing and chances were coming at the other end. John Arne Riise's raiding created a chance for Anelka, who also had an effort ruled out for offside after he had waltzed round Oakes.
It was no surprise when Owen opened the scoring on 16 minutes. Anelka's run down the right started the move, which swung to the left with Riise and then Murphy working the ball to Smicer.
A neat touch from the Czech found Owen, who spun cleverly away from Chris Riggott and scurried clear to neatly clip the ball into the net under pressure from Warren Barton and Oakes.
Liverpool had the possession but could not build on this lead before the break, despite the industry of Murphy and Steven Gerrard.
Liverpool needed to finish off Derby, because the longer the game went the more confident the Midlanders became.
Anelka should have settled things five minutes after the break. He started a flowing move with a clever ball into space for Gerrard, and when the cross was only half-cleared, the French hit-man steamed in the blaze over from 10 yards.
Anelka's involvement had been sporadic and at times isolated but he linked again to flick a Dudek ball on for Owen to chase, the little striker blasting over from an acute angle.
Oakes saved superbly to turn over a Gerrard drive and Barton produced a fine saving tackle to stop Anelka in the act of shooting.
The French striker was soon to be replaced by Heskey as Liverpool searched for the breakthrough to end Derby's resistance. But the cushion of a second would not come, with Owen wasting three later efforts.
Such was the tension that even Dudek made a mistake, fumbling a Boertein effort to the feet of Christie, and then somehow holding the follow-up effort, the two men staring at each other in disbelief.
But that crucial Liverpool second came in the last minute when another long clearance was collected by Owen. He raced away, went round Oakes and clipped the ball into the empty net to ease Anfield's collective blood pressure.