Panayiotis Tetsis was born in Hydra in 1925. In 1937 his family settled in Piraeus and in 1940 he took painting lessons with the German painter and engraver Klaus Frieslander while making the acquaintance of Pikionis and Hadjikyriakos-Ghikas. He studied at the Athens School of Fine Arts (1943 – 1949) under K. Parthenis. A year before his graduation he held his first solo exhibition (1948, Romvos art gallery).

In 1951 he started his teaching activity as a lecturer at the chair of freehand drawing at the Athens Polytechnic School, alongside professor Hadjikyriakos-Ghikas. He was granted a scholarship by the State Scholarships Foundation (I.K.Y.) and left for Paris to continue his studies at the École des Beaux Arts, where he attended copperplate classes under Ed. Goerg (1953 – 1956). Following his return to Greece, he settled in Athens and taught at the Design Department of the Athens Technological Organization (1959 – 1962). He and Eleni Vakalo, Asadour Baharian and Frantzis Fratzeskakis founded the Free School of Fine Arts (today’s Vakalo College), where he also taught (1958 – 1976). In 1976 he was elected professor at the Athens School of Fine Arts. He held his position until 1991 after having been elected rector in 1989. In 1993 he became a full member of the Academy of Athens and in 1999 he was presented with the medal of the Grand Commander of the Order of the Phoenix.

He held more than 90 solo exhibitions and took part in several group exhibitions in Greece and abroad. He participated, among others, in the Sao Paulo Art Biennial (1957) and the Alexandria Biennial (1959). Large retrospective exhibitions of his work were held while he was still alive (1992, Pieridis Gallery, which was also held at several municipal galleries in Greek cities and was followed by a retrospective exhibition at the National Gallery (1999), in Florence, Cyprus and elsewhere). He also published art studies and often wrote newspaper articles. Panayiotis Tetsis died in 2016 at the age of 91.