An antiques roadshow through Tasmania has unearthed a painting by Australian artist Arthur Streeton.

Charles Leski of Leski Auctions this year started conducting travelling roadshows where people present their treasures for valuation, similar to television versions of the concept.

His most recent trip to Tasmania paid off for one Hobart family.

"They thought one of their paintings may be by 'someone famous'," a Leski Auctions statement said.

"It turns out to be an Arthur Streeton - one of Australia's foremost landscape painters."

Streeton was a co-founder of the Heidelberg School along with such famous names as Tom Roberts and Frederick McCubbin.

The Rose Garden, believed to date from 1913, is oil on canvas measuring 60 by 50 centimetres. It is initialled in the lower left corner AS.

A Streeton painting - Sunlight Sweet, Coogee - sold for $2.04 million in May 2005.

That painting became only the second painting by an Australian artist to exceed $2 million. That distinction lies with Frederick McCubbin's Bush Idyll.

"The Rose Garden is a lovely example of Streeton's distinctive style which he seems to have mastered during his time in England," Mr Leski said in the statement.

"Streeton is highly sought after by collectors."

The Rose Garden will be offered for sale by Leski Auctions in Melbourne on December 15.

View the online catalogue Australian Art Auction