The decision taken by the administrative court in Lille came after 11 NGOs had lodged a legal complaint last week against Calais authorities who have barred them from handing out food rations to the hundreds of migrants sleeping rough around the area.
In a statement the judge said: “It is not possible to leave these people, who are in a state of complete destitution without any aid.”
Judges gave officials a maximum of 10 days to establish drinking fountains, toilets and showers to migrants exposed to “inhuman and degrading conditions”. If not Calais authorities would be subject to €100 a day fines.
The court also said officials must allow charities to hand out meals to migrants and refugees.
However Calais mayor Natacha Bouchart said the Town Hall would be appealing the decision.
There are believed to be some 600 migrants sleeping rough in various parts of Calais in the hope of trying to smuggle themselves across the Channel to Britain.
However the court ruled that it was against opening a new centre for migrants in the port town, backing the statement from the French Interior Minister last week who said there would be no new Jungle.
"We've seen this before, it starts with a few hundred people and ends with several thousand people who we can't manage," Collomb said as he met with security forces, officials and aid workers in Calais.
"That's why we don't want a centre here."