Ms Gillard is in the South Korean capital for her first Group of 20 leaders summit.
This year marks the 60th anniversary of the start of the Korean War and the prime minister will be joined by a small group of Australian veterans, as well as Canadian Prime Minister Stephen Harper, British Prime Minister David Cameron and a French minister at the ceremony.
Ms Gillard will later hold a bilateral meeting with Mr Harper, followed by a speech to a business summit.
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She's expected to discuss trade and other issues with Russian president Dimitry Medvedev before the official welcome reception and G20 leaders dinner.
