Dionysiou went to work as a tailor and was married, at age 20, to Georgia Laveni. The couple would have four children. While still working as a tailor, he also appeared in night clubs in Thessaloniki where he had moved.
Dionysiou left Thessaloniki for Athens to further his singing career. He appeared in Nikaia night club "Asteras" with well-established singer Kaity Grey and in 1959 recorded his first song. The 24-year old singer was signed by recording company "Columbia" and started singing songs by Babis Bakalis, Kostas Virvos and others with some success. He next re-recorded older songs by laika masters such as Vasilis Tsitsanis, Yiannis Papaioannou, Giorgos Mitsakis and Manolis Chiotis. Success, however would not come until the late 1960s when he turned several Akis Panos songs into hits: "Και τι δεν κάνω" (What don't I do for you), "Γιατί καλέ γειτόνισσα" (Why, my good neighbour?), "Του κόσμου το περίγελο" (The laughing stock of the World), "Εγώ καλά σου τα 'λεγα" (I told you so), "Στο σταθμό του Μονάχου" (At Munich Station), "Ήταν ψεύτικα" (They were false) and many others.
Composer Mimis Plessas then came into the picture and gave him his mega hit "Βρέχει φωτιά στη στράτα μου" (Fire is raining down my path), a song whose lyrics were written by Lefteris Papadopoulos. Dionysiou toured the United States with great success and was going from strength to strength when his career was abruptly haulted by his arrest on weapon- and drug-related charges. He was sentenced to two years imprisonment which he served in Tiryntha, Argolis prefecture.
Dionysiou recorded even in prison and continued after his release in 1976. He successfully switched from laika to a more western "elafro-laiko" type of music and enjoyed great popularity even with the younger crowd into the 1980s.