Ms Schiappa said the government "decided to set the age at 15" after consultations with doctors and legal experts. She said a new law would be presented to the Council of Ministers - France's equivalent of a Cabinet - on March 21, according to local media reports.
Current laws in France criminalize sex with children under the age of 15 but prosecutors must prove that the sexual act was forced, the BBC reported.
Under the existing legislation, if there is no violence or coercion proved, offenders may only be charged with sexual abuse of a minor and not rape.
It has a maximum sentence of five years in prison and a fine of 75,000 euro ($87,000).
Sentences are the same for sexual assaults of minors and non-minors, but rape convictions carry much harsher punishments.
The government is to approve the new age limit as part of a package of other laws against sexual violence and harassment in the coming weeks.
Minister of Solidarity and Health Agnes Buzyn said setting a legal age of sexual consent would allow a "collective awareness" and that everyone would see what was "legal and illegal", Le Figaro newspaper reported.
In November 2017, a 30-year-old man was acquitted of rape after a court determined his 11-year-old victim had not been subjected to "constraint, threat, violence or surprise".
In another case, a court initially said a 28-year-old man should face charges of sexual assault, and not rape, after saying the victim was "not physically forced to have sex".
But the same court reversed its decision last month, saying the accused should face rape charges.