'I played great. I'm speechless,' said Owen, who became the eighth different first-time winner on the European Tour in 2003. 'I was always wondering. I'm just glad I can learn from these experiences and hopefully go further now.'
Owen opened Sunday's final round with a four-stroke lead and things never got closer than two shots. He ran home a five-foot birdie putt at No. 2 but stumbled a bit at the third when he missed the green and failed to convert a seven-foot par save. Owen sank a 20-foot birdie putt at the sixth to move his margin to three strokes.
Poulter cut the gap to two shots when he drained a five-foot birdie putt at seven but Owen extended the lead a few moments later when he tapped in a two-footer for birdie.
Owen pushed his lead one hole later with a 10-foot birdie putt. After the pair made the turn, Poulter dropped shots at the par-5 12th and another at the 13th. The tournament was basically over at this point as Poulter had fallen five shots out of the lead.
'I managed to calm down and make some good birdies just before the turn,' said Owen. 'Rather than me making birdies, there was a couple of mistakes by Ian and he let me in and calmed me down a little bit.'
Owen struggled coming into the clubhouse. At the par-3 15th, Owen sailed over the green but chipped to 15 feet. Owen nearly made the par save but came up short and bogeyed two in a row when his approach came up short of the putting surface at the 16th.
Owen had one good stroke left in him and it came out at the par-5 17th. He reached the green in two, some 12 feet from the hole and two-putted for birdie.
The 31-year-old new father missed the green right at the last hole but chipped to four feet. Owen missed the putt but still had four more swipes before the tournament would be in jeopardy. He tapped in the bogey to polish off his 71 and finally break into the winner's circle.
Owen's closest brush with victory on tour came earlier this season at the Open de Portugal. He held a three-shot lead heading into the weekend but played poorly and tied for fifth.
'Portugal hurt,' said Owen. 'I scrambled my way in and it shows that I can at least hang in there when I need to. I just tried to hang on in there.'
Poulter, the winner of last week's Wales Open, shot a 2-under 70 for his second consecutive runner-up finish in this event. In 2002, Poulter battled good friend Justin Rose down the stretch but this year, he was never a factor despite a third-round 63.
Cevaer birdied his final two holes Sunday to shoot a 4-under-par 68. The tie for second matched his best finish on the European Tour as he took a solo second at the Madeira Island Open way back in 1995.
Darren Clarke had the round of the day Sunday with a 6-under 66. That moved him into a tie for fourth with Robert Rock and Anthony Wall at 8-under-par 280.
With the U.S. Open next week at Olympia Fields, Clarke can take some encouragement from his final round as he prepares to win his first career major championship.
'It was nice to shoot a good number as I go off to the states tonight,' said Clarke. 'I've been playing very good from tee to green. If I'm going to have any chance next week, I've got to sharpen up around the greens. I haven't been doing that.'
Raphael Jacquelin (67), Stephen Gallacher (70), David Lynn (73) and Jorge Berendt (70) shared seventh place at minus-7. Berendt did not leave the British Masters empty-handed as he won a new Jaguar thanks to knocking his tee ball less than three feet from the hole at 18.