Antoine Maisondieu was born in 1969 in Grasse, the historic capital of French perfumery, into a family with deep ties to the raw-materials side of the trade — his father directed fragrance ingredient laboratories, including stints at Charabot and Biolandes. His mother, Catherine Camus, is the daughter of the writer Albert Camus, making Maisondieu the novelist's grandson, a lineage he has discussed openly in French press interviews as a cultural backdrop rather than a route into fragrance.

He did not set out to become a perfumer. After moving to Paris as a teenager, he earned a master's degree in international economic law in Nice in 1993 and began, without finishing, a degree in art history. A formative internship around 1994 with Jacques Chabert — the perfumer behind Chanel's Cristalle and Guerlain's Samsara, and a friend of his father's — introduced him to raw materials and redirected him toward scent. In 1995, at age 26, he enrolled at the École Supérieure de Parfumerie Givaudan in Grasse, entering the house where he has built his career.

At Givaudan, Maisondieu rose to senior perfumer and became one of the more prolific noses working across both mass-market and niche perfumery. His commercial signatures include Giorgio Armani's Armani Code and Burberry Brit for Men, and his broader portfolio spans Prada, Valentino, Tom Ford, Bottega Veneta, Montblanc, Acqua di Parma, Van Cleef & Arpels, Comme des Garçons, and Etat Libre d'Orange, among others. In 2024 he shared the Fragrance Foundation Award for Fragrance of the Year – Men's Prestige for Yves Saint Laurent's MYSLF, composed jointly with Daniela Andrier and Christophe Raynaud.

Maisondieu describes his method as instinctive and personal rather than trend-driven, favoring strong, direct concepts built around bergamot, jasmine, iris, cedarwood, sandalwood, and other naturals handled with an emphasis on emotional resonance over reference to prior work. He is married to fellow perfumer Shyamala Maisondieu, with whom he has spoken about a complementary creative partnership.