Carlos Giménez spent a big part of his childhood in a Spanish orphanage. He started his comics career as an assistant to Lopez Blanco. His first solo works were published at Éditions Maga in the early 1960s, like the 'Buck John' series. After working for the Selecciones Illustradas agency in Barcelona, he started his series 'Gringo' with Manuel Medina, and 'Delta 99' with Flores Thies. In 1968, Giménez began working for the German market through Studio Ortega, for which he illustrated several series, such as 'Tom Berry' for Pabel Verlag, and 'Kiko 2000' and 'Roy Tiger' for Bastei Verlag.
In 1969, he began the science-fiction series 'Dani Futuro' along with Victor Mora in Gaceta Junior. This science-fiction comic soon found its way to the French magazine Tintin. In 1975, he completely changed his style, and began the autobiographical series 'Paracuellos' in Muchas Gracias. He also began a series describing the first years of democracy in his country in 'El Papus'. These stories were collected in the albums 'España Una...', 'España Grande...' and 'España Libre!'. He teamed with Alfonso Font and Adolfo Usero in 1978, and they began the 'Dossieres Mystère' series in Pif under the collective name Premia 78. He also did several one-shot comics, such as 'Hom, Koulau el Leproso', 'Erase una Vez el Futuro' and 'Koolau le Lépreux'.
Continuing his autobiographical work, Giménez created 'Barrio' and 'Los Profesionales' in the Spanish El Papus and the French Fluide Glacial magazines. He also drew 'Bandolero' in Totem. In 1990, he teamed up with Christian Godard and illustrated 'Une Enfance Éternelle'. He also started 'Coco, Facho and Co', a series of political gags.