Tanglewood owners Hamish and Caroline Hume said they were delighted with the win.
"It's the second year in a row we've won that trophy," Mrs hume Said.
"It's great it has done so well."
Their viognier also won a gold medal at the prestigious Qantas Wine Show of WA in 2010 and has won Best White Wine at the Blackwood Valley WA Boutique Wine show for three years in a row.
"Quite a few judges have said the viognier is perfectly suited to our climate here in the Blackwood," Mrs Hume said.
The viognier grape produces a complex and well structured wine which has a crisp dry finish and has strong floral and honeysuckle
perfume with hints of jasmine and ginger.
"It's got so much body. I like to call it luscious - it's a luscious wine," Mrs Hume said.
"It's a great variety and it's something a bit different - because it is an unusual variety of an edge."
Despite their critical acclaim, Mrs Hume said it was difficult to be a small wine producer and finding suitable markets for wine
or good quality grapes.
"We know lots of people who have pulled their vines out or have just shut down."
Tangledwood do not operate a cellar door and much of their wine is exported to Asia, mainly the Philippines.