He was born in Lefkochora, Messinia in 1914. He studied painting and sculpture at the Athens School of Fine Arts under U. Argyros, K. Parthenis and T. Thomopoulos. In 1933 he joined Y. Kefallinos' new printmaking studio, from which he graduated in 1939. He had already presented his first solo exhibition in 1936 (Eleftheroudakis bookstore, Athens). In 1940, he was among the students of Kefallinos who created propaganda posters for the Greek-Italian war. During the Occupation he continued to create posters and illegal resistance print material. From a young age he joined the Communist Party and he was a founding member of the Artists National Liberation Front.
Since 1939, he illustrated books and magazines. In 1948 he became artistic director of the lithography studio Aspiotis-Elka and began illustrating textbooks for the School Textbook Organization (OESV). From 1954 to 1967, while working for the Greek Post Office, he implemented innovational techniques on stamp design, and from 1962 he started designing the stamps of Cyprus. In 1959 he was appointed director of the Department of Graphic Arts at the Athens Technological Institute, where he taught until 1967.
His printmaking work was influenced primarily by the interwar standards, and themes such as the war, the occupation and the resistance were mostly reflected in his work. After the liberation, he expanded to more neutral subject matters, such as still lifes, nudes, etc. (colored or black-and-white woodcuts). During his mature printmaking period, since the '60s, he creates large woodcuts and less often wood engravings, highlighting the contrast of black and white in monumental compositions with human figures. His oeuvre is distinguished for its technical and artistic excellence, the artist’s personal interpretation of traditional forms, and a humanitarian dimension, which often takes the form of social protest (as in the works created during the dictatorship, 1967-1974).
He was a founding member of the art group Stathmi (1949) and the Panhellenic Cultural Movement (1977). He was awarded printmaking prizes and medals in Greece (1938, 1940, 1964), as well as in Krakow, Poland (1966). He has also been awarded several times for his book and album illustrations. He was an honorary member of the Academia del Disegno in Florence since 1963 and a member of the board of the Athens National Art Gallery in 1976.
He presented 18 solo exhibitions in Greece and abroad and participated in international art fairs and festivals (Venice Biennale 1950, Sao Paulo 1961) and in most Printmaking Biennales (Lugano, Ljubljana, Tokyo, etc.). He presented retrospectives exhibitions in 1953 (Newspaper To Vima), in 1964 (Athens Technological Institute) and in 1975 (Athens National Art Gallery). After his death (Athens, 1985), a retrospective exhibition of his oeuvre was organized at the Athens National Art Gallery and the Vafopouleio Cultural Center in Thessaloniki (1987).
The A. Tassos Society of Visual Arts was established in 1986, in order to disseminate his oeuvre and promote greek printmaking and was based at his house in Athens (at the Mets district), which was converted into a museum.