The tournament hostess and favourite Annika Sorenstam, playing on home soil for the last time before stepping away from competition in December, shot a final round 72 at Frösåker Golf and Country Club, one hour from Stockholm.
She ended the week in a share of sixth place on seven-under-par with three other Swedes: Lotta Neumann, Louise Friberg and Anna Nordvist, who was the leading amateur for the second week in a ro w following the Ricoh Womens British Open at Sunningdale.
Yang came from four shots behind the second round leader Lill Saether of Norway to claim her third Ladies European Tour victory, although the first was when she was a 16-year-old amateur, at the 2006 ANZ Ladies Masters. Her maiden professional victory was at the HypoVereinsbank Ladies German Open at the beginning of June.
She finished on a three-round total of 14-under-par 202. Minea Blomqvist also fired a 63 and finished in a four-way tie for second place on eight-under with Melodie Bourdy of France (66), Swedens Maria Hjorth (72) and Saether (73).
I didnt think I would win this tournament, said Yang, who moved from the Gold Coast in Australia, where she lived for three years, to Orlando, Florida, early in the season. I was just playing one shot and one hole at a time so I didnt think about my score.
Yang posted 10 birdies in total, with just one three putt bogey, at the second hole. She sank birdie putts from 25, nine and six feet at the third, fourth and fifth holes respectively and then chipped and putted for birdie at the par-five eighth going out.
As the equal leader on eight-under-par at the turn, Yang birdied three holes in a row from the 10th to grab a three shot lead over a chasing pack. She then birdied the final three holes for an inward total of just 30 strokes.
She leapfrogged her favourite player Sorenstam, with whom she was paired for the first two rounds. Sorenstam is a role model to Yang, who is also inspired by her compatriot Se Ri Pak.
Of course all the Korean golfers like Se Ri because she is like Annika is in Sweden. I like Annika too. I like the routine and the way she plays; I really like it. I think I was 10 or 11 and I watched Annikas game on the TV. I didnt think I would play with her when I grew up! It is very exciting, she said.
Everyone wants to be the number one golfer, dont they, like Annika did. Im not looking at that now. This year Im trying to get more experience. In five years maybe I can go for it.
Sorenstams Swedish farewell tournament did not go as planned. She led by one stroke after a first round of 66, but after Fridays play was cancelled due to a water logged course, she couldnt keep the momentum going through the weekend.
I played very, very well the first 14 holes and then I hit it in the water on 15 and got very deflated at that point, said Sorenstam after her final round.
Having reached eight-under at the turn, she dropped a shot at the par-four 15th hole. She eagled the par-four 17th to get to nine-under-par but then took a double bogey six at the last.
I didnt finish on a very high note so it takes the life out of you a little bit, she said. The support has been great and its been nice to have all the family and friends here. We are going to have a nice dinner tonight and that might be more emotional than out here.
Sorenstam will make her last appearance in Europe at the Nykredit Masters in Denmark, from September 5-7, before making playing her final tournament at the Dubai Ladies Masters from December 11-14.
She remained positive about winning before her return to Europe. She said: Im hoping to win next week and then the week after that; Im so due.