"If we don't qualify for Euro 2008, it's over," the 35-year-old Barcelona defender, who has played 134 internationals, said.
France lead Group B and need only a draw in Ukraine next week to advance. They could travel to Kiev already qualified if Italy beat Scotland in Glasgow on Saturday.
"The Ukraine match could mark the end of my adventure," said Thuram.
"There has to be one last match. A final of Euro 2008 which we would win would obviously be a better ending."
The Guadeloupe-born Thuram lifted the 1998 World Cup with France and was a member of their Euro 2000-winning team.
(Writing by Patrick Vignal; Editing by Peter Rutherford)
