Labour Minister Myriam El Khomri said they nevertheless undermined the French republic's promise of equality
Between April and July this year, a consulting firm commissioned by the labour ministry tested 40 businesses in six cities employing more than 1,000 people.
The firm sent out 3,000 applications for 1,500 jobs advertised by the 40 companies.
In each case, the employer received two applications for the same job describing people with similar backgrounds, experience and qualifications.
The only significant -- but sometimes decisive -- difference was in the applicants' names.
The survey found that to a greater or lesser degree, 12 of the 40 companies discriminated against candidates with north African-sounding names.
When it came to interviews, for example, 47 percent of candidates with traditional French names got interviews, but only 36 percent of those with North African names were called in.
Yet the survey noted that in 71 percent of cases both candidates received the same treatment, whether it be positive, negative or just no response at all.
The government also cautioned that the sample was too small to generalise for all French companies.
But Labour Minister Myriam El Khomri said they nevertheless undermined the French republic's promise of equality.
"These tests, of an unprecedented scale, clearly show a striking inequality of treatment in hiring," she said.
Manuel Valls, who last week stepped down as prime minister to launch a bid for the presidency, has spoken out about discrimination against citizens of foreign descent.
The Socialist party heavyweight has denounced what he calls "spatial, social and ethnic apartheid".
Anti-racism campaigners in France have for years campaigned for laws forcing employers to accept anonymous resumes that leave out details which might lead to discrimination.
A recent poll carried out by Harris Interactive for a federation of anti-racist groups suggested that more than 70 percent of people in France, Germany and Italy backed the idea of anonymous resumes.