Melissanidis was born in Munich, Germany to parents Evaggelos and Aikaterini, Greek nationals who were working in Germany. He has two siblings, Maria and Spiros. When Melissanidis was 2 years old his family returned to Thessaloniki, which he considers his hometown. Melissanidis began training gymnastics and classical ballet at the age of 9 and a half. His parents were not originally supportive of the idea, and, according to Melissanidis, only relented and took him to the Spartakos Thessaloniki gymnastics club after he refused to eat for two days. At his first Junior European Championships in 1991 Melissanidis placed a modest 18th in the all-around, but earned a bronze medal on the floor exercise, placing ahead of future World Champions Ivan Ivankov and Yordan Yovchev. Two years later, in 1993, he won the floor title at Junior Europeans and placed third on the vault. In 1994, his first year competing as a senior, Melissanidis enjoyed success on the world stage. He won the floor exercise title at the 1994 European Championships in Prague. At the 1994 World Championships he tied with Great Britain'sNeil Thomas for the silver medal on floor. With this win, Melissanidis became the first Greek gymnast, male or female, to medal at the World Championships. Melissanidis' fortunes changed after 1994: at the 1995 and 1996 Worlds he did not qualify for a single event final. However, at the 1996 Olympics in Atlanta, Melissanidis was the surprise winner of the floor exercise gold medal, winning the event with a score of 9.850. The win marked the first Olympics gymnastics medal for Greece since 1906. Melissanidis continued competing after 1996, winning the vault title at the 1998 European Championships in Saint Petersburg. He represented Greece at the 2000 Summer Olympics in Sydney, but, struggling with injury, competed only on vault and high bar. In 1996, Melissanidis publicly came out as gay.
Skills
Melissanidis has two vaults named after him in the Code of Points; both are variations of the Yurchenko double back. In the current Code of Points, his vaults carry A-score difficulty ratings of 5.2 and 5.6.
Post-retirement
In recent years, Melissanidis has been active in various social and athletic causes. He is a supporter of Greenpeace, and, in 2003, publicly supported the Melina Mercouri Foundation's campaign to return the Elgin Marbles to Greece. A gymnastics hall in his hometown of Thessaloníki has been named in his honor. He was also one of the torchbearers in the 2004 Summer Olympics Opening Ceremony in Athens. As of 2008, he was a student at the American Academy of Dramatic Arts in Los Angeles. He was also an invited guest of the 2008 Olympic competition in China and toured Chinese universities as an International Olympic representative. In 2017, Melissanidis was selected by ANT1 to be a judge on the showSo You ThinkYou Can Dance.
