The government says the bill is designed to unlock France's rigid labour market and cut stubbornly high unemployment of around 10 percent -- the issue that has dogged Socialist President Francois Hollande's four years in power.
But since March 9, hundreds of thousands of people in cities around France have demonstrated against what they see as a reform weighed in favour of businesses.
With 12 months until the presidential election, the bill is likely to be the last of its size to be introduced by Hollande's government.
On Tuesday, as lawmakers begin to examine the bill, unions and student organisations held another demonstration outside the National Assembly parliament building.
Unions fear it will erode the cherished rights of workers on full-time contracts, while student organisations -- who have been at the forefront of the protests -- believe it will fail to create "real" jobs for young people.
In response to the opposition, the government has watered down its original proposals, with the result that employers are now worried.
"In its current state, the bill really scares us," he told RTL radio.
"I would really like the lawmakers to go back to the initial spirit of the bill.
"This labour market needs to be unlocked. The whole world says so, Brussels says so and all the international organisations say so," he said.
Labour Minister Myriam El Khomri will attempt to address those concerns when she speaks to parliament at the start of the debate around 1500 GMT.
Police are bracing for fresh clashes with protesters after many of the demonstrations against the bill descended into violence.