"It's a sad end but my body can't respond anymore," Michalak, who left the pitch with a thigh injury after 11 minutes at the Millennium Stadium, told French media.
The 33-year-old Toulon player, who was groomed at Toulouse and had two stints with the Natal Sharks, won 77 international caps and played in three World Cups, in 2003, 2007 and this year.
He is under contract with Toulon until 2016.
France lock Pascal Pape is also retiring from internationals but captain Thierry Dusautoir, the 2011 world player of the year, declined to comment when asked on Saturday if he had played his last game for France. Michalak, France's leading point scorer, struggled at the World Cup, being replaced after 55 minutes in a 24-9 defeat by Ireland in their Pool D decider.
He picked up a thigh injury against New Zealand on Saturday when his clearance kick was charged down, leading to the All Blacks' first of nine tries.
One of France's most gifted players, Michalak never shone at crucial moments for his country despite winning two European Cups and two French titles with Toulouse.
He scored 23 points during a 43-21 quarter-final win over Ireland at the 2003 World Cup in Australia but had a poor game in a rain-drenched semi-final against eventual champions England in Sydney.
Four years later in Cardiff, after coming on as a replacement, he set up the try which led to France's upset quarter-final win over New Zealand.
He was not selected for the 2011 tournament when France lost to New Zealand by one point in the final in Auckland.
(Editing by Ed Osmond)
