The 18-year-old beat strong rivals from Hong Kong, Singapore and Vietnam, including Leung Isabella, Chen Callista and Nguyen Thao My.
The newly-crowned champion also overcame a wrist injury during the second round to take the title.
Hanako has been playing golf competitively for more than four years. Her biggest achievement came in 2016, when she won the Ladies’ National Amateur Championship (VLAC 2016) in Thanh Hoa Province.
She also claimed first prizes at the Vietnam Junior Open and the Saigontourist Golf Tournament in 2017.
The event attracted the participation of 80 golfers from home and abroad.
The National Sports Administration is in the process of selecting the country’s top golfers to compete at the upcoming Asian Games in Indonesia in August.