Clarke, a mountain of a man from Northern Ireland, shot a flawless 67 over Hamburg's Gut Kaden course to go into the last day three shots behind Langer.
Langer made an error at the final hole by dropping a shot, but still finished with a 70 for a three-round total of 204, 12 under par. The South African Wayne Westner is third, a further stroke adrift.
Clarke has twice finished fourth, most recently in Monte Carlo where he led by five shots at half-way but eventually lost out to the brilliance of Ian Woosnam.
Now the 6ft 2in Irishman, who weighs in at around 16 stone, hopes to put that experience to good use. A hefty cheque will put Clarke into the top 50 in the European Order of Merit and ensure him a place in the Volvo Masters at the end of the season.
Clarke's immense power helped him extract birdies at three of the par fives, while he holed from 15 feet and 25 feet at the fifth and 16th to fashion halves of 33-34.
Langer, three shots clear going into the third round, notched four birdies but they were offset by two mistakes.
Westner, the runner-up to Nick Faldo in the Irish Open, forced his way into contention with a blistering finish of four successive birdies in a best-of-the-day 66.Reuse content