Ventura last week turned 75, the age at which all bishops are obliged to hand in their resignations to the pope. Francis sometimes accepts them quickly, as in Ventura's case, and sometimes keeps people in their jobs longer.
French authorities opened an investigation into Ventura in January after a junior official at Paris City Hall accused him of molestation.
The Vatican lifted Ventura's diplomatic immunity in July so he could be questioned by prosecutors.
Ventura has not commented on the allegations.