Mrs Clinton flew into Western Australia amid massive security, for this week’s annual Australia-United States Ministerial (AUSMIN) meetings.
A motorcade of 11 cars and three buses met Mrs Clinton, along with Defence Minister Stephen Smith and Foreign Minister Bob Carr, West Australian Premier Colin Barnett and Australian ambassador to the US Kim Beazley.
Prime Minister Julia Gillard will lead talks with the US delegation, having arrived separately in Perth on Wednesday.
AUSMIN is the highest-level forum for Australia and US consultation on foreign policy, defence and strategic issues.
After AUSMIN, Mrs Clinton is to travel to Adelaide to meet Australian business leaders and visit Techport Australia, as well as pay a visit to family friends.
While here, talks will cover a sweep of regional issues important to both nations, but a main focus will be the potential increase in the American military presence at northern Australian airbases, which could also mean a higher rotation of US marines through Darwin.