Kyriakou was born on August 17, 1944, in Agiochori, Serres prefecture. He played his football for local club Doxa Sitagres before making the big jump to Apollon Athens in 1964. Kyriakou was a prolific goalscorer nearly winning top scorer honours in 1966. He came to captain Apollon with whom he stayed until 1972. He ended his career with Ethnikos Piraeus in 1975. Over all, he made 281 Alpha Ethniki appearances.
Kyriakou was capped twice in his playing career by the National Football Team of Greece.
After his playing days were over, he tried his hand at coaching without much success.