The 2009 Australian Open Men's singles final was the championship tennis match of the Men's singles tournament at the 2009 Australian Open. It was contested between the world's top two players for much of the previous four years, Rafael Nadal and Roger Federer, then ranked first and second in the world respectively. It was their seventh of nine meetings in a major final, and their first outside of either the French Open or Wimbledon. This was Nadal's first major hard court final, while it was Federer's ninth and at the time he was yet to lose in a major hard court final.

The tennis rivalry between Roger Federer and Rafael Nadal is considered one of the greatest in the history of the sport. Federer and Nadal played each other 40 times, with Nadal leading 24–16 overall, including 14–10 in finals.