The farmers say meetings with Agriculture Minister Stéphane Le Foll have proved fruitless.
They maintain their livelihoods are threatened by competition from abroad and a reduction in EU subsidies.
Among those protesting were dairy farmers worried about an EU plan to end their subsidies.
Fruit growers, crop farmers growing rice as well as those who raise bulls for bullfighting, sheep farmers and those who produce hay in the Crau plains all complain that their subsidies are being severely reduced.
They say they want “answers” from the government and point out that some of their activities form part of the cultural life of the Camargue region near Marseille.
Meanwhile the president of Marseille port authority condemned the farmers’ action.
“The blockade which affected the port has severely impacted on our customers and therefore to the whole port. Activity was at a standstill for several hours at a time when all our energy should be devoted to developing this port”, said a statement from the port authority.
The agricultural workers say the deliberately chose the port area for their protest because most of the imports which they say are threatening their livelihoods transit through the port.