A penthouse in Melbourne has been sold for A$25 million to an unnamed China businessman, becoming the highest price paid for an apartment in Australia, Singapore-listed Aspial Corporation said on Thursday.

The 750 sq m penthouse is located in the highest residence in the southern hemisphere called Australia 108, the jewelry company said in a filing to the Singapore Exchange.

The unit is located 319m above street level and was bought by an "international businessman" based in China, it said.

The project is being built by Aspial's property arm World Class Land.

The sale "raised the bar for price per square metre in Melbourne, with the apartment costing more than A$33,000 per square metre," Aspial said. "Contracts have been exchanged and a 10 per cent deposit has been paid by the purchaser who will use the penthouse as his private residence when in Melbourne each year."

The announcement said the penthouse will boast 360 degree views of Melbourne and span the entire top floor. It will be completed in 2019.