Jean-Claude Ellena was born in 1947 in Grasse, the historic center of French perfumery, into a family with roots in the trade. As a teenager he began working at the Antoine Chiris essential-oils factory in Grasse, and in 1968 he became the first enrolled student at the newly founded Givaudan perfumery school in Geneva, the start of a formal training that grounded him in classical materials and technique.

After years composing for major fragrance houses and manufacturers, including an early hit with Van Cleef & Arpels' First in 1976, Ellena built a reputation for a spare, transparent style that favored a handful of well-chosen materials over dense, layered compositions. In 1990 he was a founding member of the Osmothèque in Versailles, the archive dedicated to preserving historic perfume formulas, and in the 1990s and early 2000s he composed for Bulgari and other houses while also running his own label, The Different Company.

From 2004 to 2016, Ellena held the rare position of exclusive in-house perfumer for Hermès, a role in which he created the multi-part Hermessence collection sold only in Hermès boutiques and mainstream successes such as the Jardin series and Terre d'Hermès, the men's fragrance that became one of the house's best-selling scents. During and after his Hermès tenure he also composed for independent niche labels, notably several fragrances for Frederic Malle's Editions de Parfums.

Since 2019, Ellena has served as Director of Olfactory Creation for the French house Le Couvent Maison de Parfum, overseeing a signature collection alongside collaborations with younger perfumers. He is also a published author, having written books on the craft and philosophy of perfumery, and is the father of perfumer Céline Ellena and brother of perfumer Bernard Ellena, making him part of a multi-generational perfuming family.