Julie, playing out of Kings Acre Golf Centre, near Edinburgh since she left Loretto School, finished the 72-hole event on four-under par 284.
Apart from the major trophy, Julie also came away with the Under-18 and Under-23 English titles which were at stake.
Since she arrived in Scotland from Phoenix, Arizona last September, Julie has won the Welsh women's amateur stroke-play title, the Paul Lawrie Scottish schoolgirls championship and the Danish women's open amateur title.
"I am very pleased. In the mid-summer you are constantly playing and winning one tournament helps you with the next one," said Yang.
"It's like a chain, if you have a good tournament you feel there's a chance the next one will also be a feelgood time."