Rialto (often The Rialto, or Rialto Towers) is a skyscraper located at 525 Collins Street, in the western side of the Melbourne central business district, Victoria, Australia. It was the tallest office building in the Southern Hemisphere when it was constructed.

The Rialto featured Melbourne's first skyscraper public observation deck, which operated between 1994 and 31 December 2009.[2] It was also the location of Melbourne's first Tower running event.