Natacha Bouchard's mayoral decree outlawed the "regular, persistent and large presence of individuals distributing meals to migrants," as well as any "repeated, prolonged gatherings" in the area.
The Mayor of Calais also said that encouraging migrants to stay there could create safety risks for the area.
The move comes after French authorities demolished the 'Jungle' migrant camp in Calais last year, with the migrants being brought to other parts of the country to apply for asylum.
Charities have criticised Natacha Bouchard's order and have vowed to continue helping migrants in Calais, though they will check to see whether they are legally able to do this first.
Speaking on Premier's News Hour Phil Kerton, from Seeking Sanctuary, said: "The Mayor of Calais finds herself in an election year in France. The political parties are trying to outdo each other in saying and doing more and more inhumane things.
"I think we need to pray for God's protection for them [the migrants], and at this season of Lent a change of heart - a conversion to help the people who are there who are in need.
"All the aid agencies in Calais signed an open letter to the Miniser of the Interior, saying that if the govermment was not going to provide for these people in dire need then they would do start doing so openly, no matter what the consequences."
Listen to Premier's Alex Williams speaking to Phil Kerton on the News Hour:
