The 25-year-old German had a 6-under 207 total in the 54-hole event at Tali golf club.
Johanna Westerberg finished second, and Lotta Wahlin was a further shot back in third. Both Swedes closed with 70s.
Hauert's next event is the Solheim Cup between defending champion United States and Europe on Sept. 14-16 in Halmstad, Sweden.
Two other Solheim Cup players, Gwladys Nocera of France, tied for 33rd at 220, while Iben Tinning of Denmark shared 41st at 221.
Dottie Ardina, a 13-year-old from the Philippines, was the best amateur in 29th place after finishing the first day in 11th. She made the cut in her second LET event.