Her training as an artist began in 1781 under Élisabeth Vigée Le Brun, and she entered Jacques-Louis David's atelier in 1786 along with her sister Marie-Élisabeth Laville-Leroux.
Benoist first exhibited in the Exposition de la Jeunesse in 1784, showing a portrait of her father and two pastel studies of heads.
In 1791, Benoist exhibited for the first time at the Paris Salon, displaying her mythology-inspired picture Psyché faisant ses adieux à sa famille.
Her career was harmed by political developments, however, when her husband, the supporter of royalist causes, Comte Benoist, was nominated in the Conseil d'État during the post-1814 Bourbon Restoration.
Despite being at the height of her popularity, "she was obliged to abandon painting"[5] and pursuing women's causes, due in part to her devoir de réserve ("tactful withdrawal") in the face of the growing wave of conservatism in European society.