"Having served as a prime minister, having been chosen by France, I solemnly accuse the prime minister and the government of failing to ensure the right conditions for a placid exercise in democracy," Fillon said in a statement on his website on Sunday.
The candidate recalled the recent events in Toulon, where dozens of people harassed another candidate, Emmanuel Macron, as well as disorder caused during National Front (FN) party leader Marine Le Pen's visit to Nantes.
Around a dozen police officers were injured in clashes in Nantes on Sunday.
Presidential candidates should have a right to express their opinions freely, he stressed, adding that the government should undertake measures against "marauders" and any enemies of democracy seeking to upset the pre-election campaigns.
"It is essential for the government to ensure conditions for successful elections. It is necessary to respect the rule of law," Fillon said.
French presidential elections are due to take place in two rounds on April 23 and May 7.
