The 40-second teaser trailer shows all 12 of the contestants who will take part in the cooking show special.
Series one alumni Justine Schofield, Chris Badenoch and Poh Ling Yeow will join MasterChef Australia's first ever winner Julie Goodwin.
Since winning the show, Goodwin has written a cookbook and appeared on programmes including The Project and Nine Network breakfast show Today.
Series two runner-up Callum Hann will be joined by Aaron Harvia, Jonathan Daddia and Marion Grasby, while the show's most recent winner Kate Bracks completes the lineup with her fellow competitors Hayden Quinn, Dani Venn and Kumar Pereira.
A fourth season of MasterChef Australia is currently airing on Ten, with the all-stars special to air over three weeks during the Olympics.