Iličić began his professional career with Slovenian club Bonifika, later also playing for Interblock and Maribor in his home country, before moving to Italy in 2010 to join Palermo.

Born in Prijedor, SR Bosnia and Herzegovina, Iličić started his career playing in the youth teams of Triglav Kranj and later Britof.

He wanted to return to futsal, his passion, and to find a job, however, a few weeks later he received a phone call from Zlatko Zahovič, the director of football at Maribor, who proposed he should sign for the club.

[7] He then scored again, in the return leg of the UEFA Europa League playoff round against Sicilian Palermo, which ended in a 3–2 win for the Slovenian side.

[12] His good performances against top Italian teams continued when he scored a goal against Fiorentina on 3 October 2010,[13][14] and against Roma on 28 November 2010.

Despite that, he was confirmed for the 2012–13 season as well, being paired with new signing Franco Brienza in a 3–4–2–1 formation by new head coach Gian Piero Gasperini.

The 2014–15 season was more successful for him, finishing as the club's top scorer with ten goals in all competitions, along with Mario Gómez.

[23] On 25 January 2020, Iličić scored a hat-trick, which included a free kick goal from the halfway line, in a 7–0 victory over Torino.

[29] After twelve years of playing in Serie A, Iličić returned to Slovenia and joined his former club Maribor on 5 October 2022, signing a contract until June 2025.

[33] Iličić missed out on the 2010 FIFA World Cup but made his debut for the senior team in a friendly match against Australia on 11 August 2010.

[35] In May 2024, Iličić was included in the preliminary squad for UEFA Euro 2024, ending his two-and-a-half years absence from the national team.

[40][44][45] His former Palermo coach, Bortolo Mutti, believed that the 4–3–3 system was the perfect formation for his characteristics, as it allowed him to be deployed on the right flank, a position from which he could cut inside and strike on goal with his stronger left foot.

[48][49] A powerful and accurate striker of the ball with either foot, in particular from distance, he is highly regarded for his touch on the ball, technique, dribbling skills, and creativity, as well as his physical strength, leadership, strong personality, and instinctive play on the pitch;[41][50][51][52][53][54][55] he is also known for his use of feints, in particular the back-heel move,[56][57][58] and is an accurate set piece and penalty taker.

[50][51][67] Despite his talent and ability, he has been accused by certain pundits of being inconsistent at times, and has also drawn criticism over his difficult character, defensive positioning, and tactical awareness, in particular in his youth, although he was able to improve on the mental aspect of his game as he matured and his career progressed, which saw him reach his prime and maintain a consistent level of performance into his early 30s.