The 24-year-old from Rhône won gold in the 400 metres freestyle at the 2004·Olympics in Athens, where she also claimed silver in the 800m freestyle and bronze in the 100m backstroke.
She announced her retirement in 2009, in the wake of disappointing results at the 2008 Beijing Games, where she finished last in the 400m freestyle, a race won by Britain's Rebecca Adlington.
"Yes, the will to resume competing is back," Manaudou told Le Journal du dimanche.
"I need time.
"We don't have an exact programme for the moment as I need some more time.
"I'm not yet at World Championship level but I will work on it.
"Every swimmer who has been to Olympics wants to return but there's a long way to go.
"First of all I need to qualify."
France's most prolific swimmer, Manaudou has won three world titles and nine European gold medals.
Her partner is top French swimmer Frederick Bousquet.
The couple have a daughter, Manon, who was born last year.
She began training again in October of last year at Auburn, Texas, and sent a letter of intention outlining her plans to world swimming body FINA meaning that she would be able to race again from July 5.
"I can sense that she is happy with the decision and that is what counts most," said Bousquet.
Five-times Olympic champion Ian Thorpe and three-times champion Libby Trickett have also returned to the pool after the Australian duo ended retirements.