Westwood began the day one shot back of 54-hole leader Padraig Harrington. But the Irishman could only muster an even-par 71 to tie for third with American Tom Gillis, who shot a final-round 69.
'I haven't been playing so well in the past few weeks, but I've worked one some things and it all came together here,' said Westwood. 'I felt very comfortable today. I hit the ball very well. That's what you've got to do here.'
Westwood won the inaugural Belgacom Open in 1998 in similar fashion. Trailing by one shot entering the final round at Royal Zoute, Westwood carded a Sunday 66 to force a playoff with third-round leader Fredrik Jacobsen, whom he defeated on the first extra hole.
This year, Westwood immediately tied Harrington at the top of the leaderboard on Sunday when the Irishman bogeyed the first. Another Harrington bogey at the third gave Westwood sole possession of the lead; and he never looked back.
Westwood carded an outward half of 32, and then added four more birdies heading home for a surprisingly easy victory.
This is Westwood's 14th-career European Tour triumph. In seven of those, the 27-year-old has shot 66 or lower in the final round.
'This year is going well,' Westwood said. 'There are still some very big tournaments to go, but I can go home tonight and enjoy this one. I felt like I won it well - as well as I have won any tournament, if not better. It couldn't have been any more than a 65 and probably could have been a couple lower.'
With his $146,000 first-place check, Westwood passes Darren Clarke, who missed the cut this week, for the top spot on the 2000 Order of Merit. Westwood now leads the Ulsterman by just over $60K.