Polychroniou was born in Platanistos on the island of Euboea, on November 12, 1936. He started his career, in 1954, as a forward but quickly turned into Olympiakos' regular defensive midfielder and long-serving captain. Among his specialties were guarding opposing forwards, the most noteworthy of which was Pele in the July 4, 1961 Olympiakos - FC Santos friendly.
After his playing career was over, Polychroniou turned to coaching and had a 4-year tenure (1994 - 1998 coaching 34 games) with the Greek National Team. Other teams he coached include Larisa FC (1979 - 1980), Rodos FC (1982 - 1983), Doxa Drama (1984), Apollon Athens (1985), Olympiakos (1993 - 1994), Paniliakos (2001).