Gary Speed's side's recent good form continues with a win in Sofia as the Welsh record their third victory in four qualifying matches
The game was played in the eerie surroundings of an almost empty 43,632 capacity Vasil Levski Stadium due to Bulgarian fans boycotting the match due to their nation's poor recent performances and rising ticket prices.
Gary Speed's side controlled much of the first half and created chances within the first ten minutes. Craig Bellamy hit a 20-yard effort at Nikolay Mihaylov and Bale also tested the former Liverpool keeper with a low shot.
Bale was quickly becoming Wales most potent attacking threat and Petar Zanev was unable to stop him advancing down Wales' right flank and crossing for Bellamy who was crowded out as he looked for the target.
Bulgaria's young team may have been keen to impress new manager Milhail Madanski and Ivelin Popov robbed Darcy Blake of possession but as he broke into Wales' penalty area, he ran out of support and was tackled.
Bulgaria began to grow in confidence, Zanev finally managed to break free of Bale and fired a cross which was cleared and a Bulgaria corner caused uncertainty but Ivanov was unable to capitalise.
The home side then had a glorious chance to score as the lively Popov broke down the right and fired the ball across the Wales area but Domovchiyski was a whisker away.
Wales were forced to make a change as Celtic full-back Adam Matthews replaced the injured Darcy Blake, Chris Gunter moving into a central role.
As the half wound down to a close, Wales hit Bulgaria with a sucker punch to take the lead, Matthews played the ball over the top and Bale ran onto the ball, cutting side and shooting past Mihaylov via a deflection off Zanev.
Wales had controlled much of the game and went in for the half-time break deserving their lead.
The Welsh came out for the second half playing some magnificent football. Bale again tormented Bulgaria down the right and played the ball to Ramsey who in turn flicked the ball to Bellamy on the edge of the box who disappointingly shot over.
Bellamy then looked to turn provider as Mihaylov fumbled his cross before another fizzed effort from the Liverpool man was just inches away from Bale, looking to score his second.
Bale came even closer to adding to the score. Ramsey juggled the ball under pressure from Bulgarian defenders and looped the ball over to bale who smashed a volley onto the underside of the crossbar, the ball bouncing out without crossing the goal line.
Bulgaria sub Spas Delev was looking dangerous as his cross was deflected over by Gunter with former Man City forward Valeri Bojinov lurking.
Wales were determined not to be pegged too far back however as Bale continued to threaten and Ramsey shot over following a surging run into Bulgarian territory.
Bulgaria were frantically searching for an equaliser Bojinov was played through but could only toe poke wide with only Hennessey to beat.
The home side's challenge eventually fizzled out and Wales picked up a victory that sees them finish fourth in Group G as Switzerland picked up a win against Montenegro to hold on to third spot.