Organizers hoped that the protests would grow further into a groundswell of support against Macron's reform of France's public service and some state enterprises such as the heavily indebted national railway company SNCF.
"We are going to carry a message (and) this message must be heard by the strong-headed Emmanuel Macron," Jean-Luc Melenchon, leader of the far left France Unbowed party, told a cheering crowd before the protest set off in the southern port city of Marseille.
Melenchon listed a number of grievances including staff shortages at hospitals, limited admissions at universities, and lack of police in tough neighborhoods, because the government says it does not have the means to fund them.
"We do not believe you because you are lying," Melenchon said, adding that Macron's government had given a 4.5 billion euros ($5.25 billion) tax break to the rich which could have been invested in hospitals.
"The country is rich. The country must share," Melenchon said.
In Paris, Police said some 30 people were arrested before the start of the march for various offences.
Holding banners and chanting slogans, protesters are expected to hold rallies in at least 160 places across France, CGT Secretary General Philippe Martinez said, adding that Macron should listen to the growing anger.
Unions have staged several nationwide strikes since the start of the year, while SNCF rail workers have been carrying out rolling strikes on two of every five days of the week since April over plans to reform the company and open it to competition.
Macron, 40, who came to power a year-ago promising to push through tough reforms, has shown no sign of surrender so far.
In comments last Friday, Macron said the so-called popular wave protest led by Melenchon would not stop him and said the opposition had failed to bring forward any concrete proposals.
(Reporting by Bate Felix, Caroline Pailliez and Emmanuel Jarry)