Paul GILLON made his debut at the age of fourteen, making cover illustrations for partitures, and doing caricatures of people from the music, theatre and cinema scene for Samedi-Soir, France Dimanche and Gavroche. In 1947, he started working for the comics magazine Vaillant, where he took over series such as 'Lynx Blanc' (from Bob Sim), 'Cormoran' (from Lucien Nortier) and 'Wango' (from E.T. Coelho), written by either Roger Lécureux or Jean Ollivier. In addition, he created series of his own, such as 'Fils de Chine' (1950-53) and 'Jérémie' (1968). Starting in 1949, he was also present in 34 Caméra, Femmes d'Aujourd'hui, Rêves and Radar with several short stories.

In 1959, he began the daily comic strip, '13, Rue de l'Espoir', in addition to his work for the magazines. The scenarios were by Jacques and François Gall, and the comic was published in the France-Soir until 1972. From 1961, his name also appeared in Le Journal de Mickey, where he made several comic adaptations of television series and films, such as 'Le Temps des Copains', 'Le Fantôme de Barbe-Noir', Teva' and 'Notre Dame de Paris'.

In 1964, Gillon began the futuristic saga 'Les Naufragés du Temps' with writer Jean-Claude Forest. The series, a masterpiece of European comics, was initially published in Chouchou, but upon the disappearance of this magazine, it was transferred to France-Soir. Gillon took on the scriptwriting of the series himself in 1977, when it made its appearance in Métal Hurlant. For the same magazine, Gillon produced 'Les Léviathans' (initially published in B.D. from 1978) and several science-fiction stories.

Gillon illustrated the historical comic 'L'Histoire du Socialisme en France', with a script by Moliterni, for the Éditions Service de l'Homme, in 1977. In 1985, Gillon appeared in Vécu with 'Au Nom de tous les Miens' (script by Patrick Cothias). For L'Écho des Savanes, he made the erotic post-apocalyptic series 'La Survivante', which consists of four episodes. Also for L'Écho, he made the comics biography of 'Jehanne', starting in 1993, as well as 'Le Contrat' in 2000.

Gillon teamed up with writer Denis Lapière in the mid-1990s to make 'La Dernière des Salles Obscures', which was published in two parts in the Aire Libre collection of Dupuis publishers in 1996 and 1998. In 2002, he made another book for this collection, called 'La Veuve Blanche'. That same year, he illustrated 'Les Conjurés', the 7th episode of the 'Le Décalogue' series by Frank Giroud, published by Glénat. For the same publisher, he created 'L'Ordre de Cicéron' with scriptwriter Richard Malka in 2004.