Mr Chirac, 74, has been president since 1995 and has had a political career spanning four decades.
"The moment has come for me to serve you in a different way," he said.
Recent polls show Interior Minister Nicolas Sarkozy has a narrow lead over his Socialist rival, Segolene Royal, ahead of the 22 April poll.
Mr Sarkozy, who has won backing from the governing centre-right UMP party, said he hoped to receive Mr Chirac's endorsement.
Mr Chirac told the nation in his Sunday evening address that he would find new ways to serve France after leaving office.
He will leave more popular than he has been for a long time
Le Figaro
French press bids adieu
"In a different way, but with the same enthusiasm, and the same passion to work for you, I will continue to take part in our shared struggles - my life struggle - for justice, for progress, for peace, for the greatness of France," he said.
The president said he was "proud of the work which we have carried out together," citing in particular improvements for the elderly and the disabled, reforms of the pension system and reductions in crime and unemployment.
And he called on France to defend its values.
"France is not a country like others. It has particular responsibilities, the legacy of its history and the universal values it helped create," he said.
"I will not seek your votes for a new mandate." With these words, the President of France, Jacques Chirac (74) announced during a radio and television broadcast at 20:00 UTC that it's time for him to serve his country in a different way.

The announcement was widely speculated about and did not come as a surprise. The official announcement gives the candidate from the majority party UMP, Nicolas Sarkozy, more freedom during the next six weeks that remain before the Presidential elections in France. Although Sarkozy is from the same party as Chirac and hopes to receive an endorsement from him, the President has not yet expressed his support for a particular candidate to succeed him, and he did not refer to Sarkozy during any moment of his speech.

In his 4 decades in French politics, Chirac has occupied several posts as Minister and was Prime Minister twice before being elected President in 1995, and being re-elected in 2002. Shortly after taking office, he acknowledged the role of France in the deportation of 75,000 Jews during World War II. After he called for new elections in 1997, he had to work with a Socialist Prime Minister, Lionel Jospin for 5 years. In 2001, France became the first country to declare slavery a crime against humanity, and Chirac decided May 10 would be a day to commemorate the abolition of slavery.

In 2003, Chirac threatened to veto a resolution in the U.N. Security Council that would approve of an invasion of Iraq. Consequently, the United States overthrew Saddam Hussein without support from the United Nations. In 2005, Chirac couldn't convince the French to approve the European Constitution in a referendum. At the end of that year, minority youths in France's suburbs rioted for three weeks.

During his address, the President also discussed the democratic values of France, his role and responsibilities, Europe and the environment.

In the polls, Sarkozy has a slight benefit over Ségolène Royal, the candidate from the Socialist Party. François Bayrou, the candidate from the centrist party UDF, has improved his positions in the polls during the last few weeks, coming up in third position by only a few points. If none of the candidates reach an absolute majority during the first round on April 22, a second round between the two candidates with the most votes will be organised. In the polls, at least 40% of voters have said they are yet undecided about their vote in the upcoming ballot.