Born in Vilassar de Dalt (Barcelona) in 1930. Son of a goldsmith, he was self-trained and first started painting in the late 1950's. His first individual exhibition was held in 1953 in the Sala de Vilassar de Dalt. From Josep Fabregas he learned perspective, and from Ramon Fort the watered-down technique. It was the Catalan painter John Agell who recommended he devote himself to watercolors. He also exhibited his work in the Picture Gallery Tot Art (Andorra), the Fine Arts Circle (Palma de Mallorca), Gifre & Escoda Gallery (Barcelona) and Sala Rusiñol of Sant Cugat.
He has received numerous prizes such as the second National Watercolor Award in Madrid in 1987, the International Drawing Award Ynglada- Guillotin Barcelona, and the Gold Medal of the Watercolor Painters Association of Catalonia. His works can be found in the Catalan Royal Academy Museum of Fine Arts of Sant jordi, the Museum Les Templiers of de Cotlluire, the Foundation Martinez Lozano (Llança) and the Municipal Picture Gallery "Llegat Francesc Gali" (Palamos). In 1993 Sala Rusiñol dedicated the book "Amadeu Casals" to him, volume II of the collection "Homenatges Rusiñol" by Francesc Gali. In 1998 the book "Amadeu Casals. Aquarel·les" was published,
by Josep M. Cadena