Bjorn shot his second straight 6-under 66 to finish at 24-under for the tournament and four clear of Langer and Bickerton.
Both Langer and Bickerton made charges early with birdies on the front side but Bjorn responded by making four of his own for an outward 32.
Bjorn, who with the victory kept his string of seasons with a win alive at five, added three more birdies on the back nine as his two pursuers never got closer than two.
I went out this morning to play as aggressive as I had all week and attack the course because I knew I needed to shoot a (low) number, said Bjrn. Down the stretch it was in my control and I knew if I didnt make any mistakes the tournament was mine.'
Langer, never a winner of the BMW Open in his home country, ran his total of runner-up finishes to a heartbreaking five, as he posted a final-round 68.
And what a wild week it was for Langer. Coming all the way from Seattle, Wash., after the WGC-NEC, as did Bjorn, a jet-lagged Langer enjoyed the home country crowds as well as an opening 64 that gave him the first-round lead. Then came a bout with food poisoning on Friday that saw him thinking of pulling out of the tournament.
Surviving the effects of his conditions, Langer managed to find himself in the final group on Sunday, only to find himself to be a bridesmaid yet again.
'Every time I made a birdie he seemed to hit back with one of his own. I holed a very long putt on the ninth but Thomas countered immediately,' Langer noted. 'I will come back next year and try and win this tournament to complete the set.
For Bjorn, who has now won the event two of the last three years, it gives him some much needed confidence heading into the Ryder Cup matches in late September. It also moves him to 13th on the Order of Merit (money list).
Richard Bland, who started the day just two strokes behind Bjorn, shot a even-par 72 to finish alone in sixth.
Ian Poulter (70) and David Park (67), came in a tie for fourth at 17-under.
Defending champion John Daly carded a final-round 69 to climb into a tie for 10th.
Full-field scores from the BMW International Open