Miljković is regularly on the top of the best spikers list in the tournaments and has a great jump serve. He is very well built and extremely strong opposite hitter who has variety of different shots; he can swing the ball away with a power or using his good technique.
For an extremely big player Miljković moves surprisingly well. He has a good footwork and is quick from his feet; therefore he is able to generate a good speed for his approach from any distance to the ball.
Scoring machine Miljković is probably the best volleyball player in the world in his position.
He started his professional career in Partizan Belgrade in 1997.
He played in the national team of FR Yugoslavia for the first time a year later (on October 4, 1998 in a game against Turkey). In 2000 in Sydney the Yugoslav national team (members of which were also Vladimir Grbić, Nikola Grbić, Andrija Gerić, Goran Vujević) won the Olympic gold medal. In the final match against Russia Ivan Miljković scored the last point and after that fell on his knees.
After this success he changed his club and started playing for Italian Lube Banca Macerata. In 2001 the Yugoslav team won the European Volleyball Championship in Ostrava, Czech Republic. With his club, Lube Banca Macerata, he also won the Champions League (2001), twice the Italian Cup (2001, 2003) and three times the CEV Cup (2001, 2005, 2006).
On July 18, 2007, he signed a contract with the M. Roma Volley. The following year, on July 5, 2008, Olympiacos, announced that he will be continuing his career in Greece. In 2009 he won the Greek Championship and the Greek Cup.
Both in the club and in the national team he wears a jersey with number 14.