Some 40 World leaders including British Prime Minister David Cameron, German Chancellor Angela Merkel and Russian Foreign Minister Sergey Lavrov are expected to attend a huge march in Paris to show unity after three days of terror that left 17 people dead.
About 2,000 police officers and 1,350 soldiers are being deployed across the French capital to protect marchers.
On Saturday, around 700,000 peaceful protesters took part in marches across the country to commemorate the victim of violence in the past week.
Most of the marches were held in silence with some protesters holding banners that read "unity".
The family of a French Muslim police officer killed in the Pairs newspaper attack also spoke out against racism.
Malek Merabet is the policeman's brother.
"To all the racists, Islamophobes and anti-Semites, extremists must not be confused with Muslims. I'd like to bring up one more point, stop confusing things, stop starting wars, burning mosques or synagogues: you are dealing with human beings here."
Meanwhile, Hundreds of people have rallied in New York City to mourn the victims of the deadly terrorist attack at France's Charlie Hebdo magazine.
The demonstrators gathered in Manhattan's Washington Square Park holding posters that read "I'm Charlie".
Matthieu Dutriaux is a French expat living in New York.
"I am from France. I am personally touched by this. I think we have to keep the freedom of expression and I want to make sure there is no misunderstanding about the attacks, the religions, the drawings. I want to make sure that people sit together, so I want to show my support."
Condolence messages have poured in from all corners of the world condemning the recent acts of terrorism in France.
