It comes as concern is expressed over violence and threats against MPs, including attacks on several offices.
Jean Michel, 76, the mayor of Signes in the Var, died after being run over as he tried to stop a van illegally dumping rubble.
The shock over his death prompted other mayors to speak out about a rise in threats, intimidation and violence.
While President Macron promised an “uncompromising” response, senators asked mayors to fill in a questionnaire to see the scale of the problem.
Mr Michel’s death showed the “insecurity many mayors faced in their day-to-day work”, the Senate Laws Committee said.
The revelation of the scale of the problem has shocked many as mayors are traditionally well respected, even by people who disagree on politics.
A poll for the Association des Maires de France found that most people (83%) respected their mayor.
Charles Scibetta, mayor of Carros in the Alpes-Maritimes, has faced threats, including a crowd of about 50 people protesting outside his house.
He said that while the vast majority of people were respectful “others feel free to say anything online then take it to the streets.
It is a worrying lack of respect and even some politicians should set a better example.”
No hero, just dedicated – see more here