Rozwój Katowice Milik began his career as a youth player for
Rozwój Katowice and played in the reserve team during the 2009–10 season. Milik failed to impress at Leverkusen though, making only 6 appearances before being demoted to the Leverkusen reserve team.
Loan to FC Augsburg On 30 August 2013,
FC Augsburg signed Milik on a one-year loan deal. The loan fee was reported to be €150,000, and composed of a base amount that decreased the more games Milik played for Augsburg and increased if Augsburg maintained its Bundesliga status. During his spell in Augsburg, he was capped in 18 matches, but he only scored 2 goals. However, he scored an equalizer in the 88th minute in a 2–2 home draw against
Borussia Mönchengladbach, helping Augsburg earn a vital point.
Ajax On 15 May 2014, it was announced that Milik would spend the
2014–15 season on loan at reigning Dutch champions
Ajax, with a purchase option of €2.8 million.
2014–15 season On 24 September 2014, Milik played in the first official
Amsterdam derby to be contested since 1983 when Ajax took on
JOS Watergraafsmeer in the
KNVB Cup. Milik earned the man of the match award after scoring six out of the club's nine goals and assisting a further two in the
Olympic Stadium. On 10 December 2014, he scored his first
Champions League goal in a 4–0 victory over
APOEL. On 1 April 2015, Ajax reached an agreement with Bayer Leverkusen to purchase Milik outright on a four-year deal for a reported €2.8 million fee.
2015–16 season On 26 June 2015, Ajax announced Milik would replace departing striker
Kolbeinn Sigþórsson as the club's number 9 for the
2015–16 season, switching from kit number 19. Milik scored his first goal that season in a
UEFA Champions League qualifier against
Rapid Wien, making the scoreline 1–2. The game was eventually lost 2–3 and the two-legged tie 4–5 on aggregate to Rapid, relegating Ajax to the
UEFA Europa League play-off against Czech side
Jablonec. Milik scored his first goal of the
2015–16 Eredivisie season against
Willem II after newly appointed captain
Davy Klaassen provided him with a cross, which Milik headed-in. Ajax went on to win the game 3–0 after a brace from
Anwar El Ghazi. In the first leg of the Europa League play-off qualifier against Jablonec, Milik scored a penalty after Klaassen was fouled in the box; the goal was the winner in a 1–0 match. During the beginning of the season, Milik also scored goals against Willem II,
NEC and
Excelsior. Nearly a month later, on 31 October, he began a scoring streak again, this time scoring two against
Roda JC in a 6–0 rout. Milik also scored league goals against
Cambuur on 11 November and
Heerenveen on 5 December, the latter in which he also missed a penalty. On 26 November, Milik scored the 1–1 equalizer against
Celtic in the
Europa League group stage, where Ajax went on to win 2–1 away in
Glasgow. On 20 December, Ajax's final match before the winter break, he also scored the opening goal against
De Graafschap in an eventual 2–1 home victory at the
Amsterdam Arena. After the winter break, Milik was out of form and got a lot of criticism, having gone scoreless in Ajax's first three Eredivisie matches. He broke his poor run of form by scoring against Roda JC on 31 January 2016 in a 2–2 away draw. On 21 February, against Excelsior, he then scored a brace, while in Ajax's next home game, on 28 February, he scored another two goals against
AZ. One week later, on 6 March, Milik scored against Willem II in an eventual 0–4 away win in
Tilburg.
Napoli in 2019 Milik signed with
Napoli on 1 August 2016; his €35 million transfer was officially confirmed by the club the following afternoon. He made his club debut on 27 August, scoring his first two goals for Napoli in a 4–2 home win over
Milan in
Serie A. He scored braces again against
Dynamo Kyiv and
Bologna in September, but on 8 October, Milik tore his anterior cruciate ligament in a Polish international fixture against Denmark and was expected to be out for the rest of the season. However, as of 12 February 2017, he resumed playing and was fielded again on 15 February in the
Champions League match against
Real Madrid. In the
2020 Coppa Italia final on 17 June, following a 0–0 draw after regulation time, Milik scored the winning spot kick in a 4–2 penalty shoot-out victory against
Juventus. In the 2020–21 season, after having decided not to extend his contract and at the same time rejected a number of transfer options, Milik was excluded from the official Serie A and UEFA Europa League squads.
Marseille On 21 January 2021, Milik joined
Ligue 1 club
Olympique de Marseille on an 18-month loan deal with an obligation to buy. He made his debut in a 3–1 loss against
Monaco on 23 January. On 17 October 2021, he scored his 10th goal for Marseille in his 17th appearance in a 4–1 win against
Lorient becoming the most efficient goalscorer for the club since
Sonny Anderson in the
1993–94 season. On 19 December 2021, he scored a hat-trick against
Cannet Rocheville in a 4–1 Marseille win, helping his club advance to the round of 16 in the
Coupe de France. On 31 January, he scored another goal for the club in a 1:1 draw against
Montpellier HSC helping Marseille to advance to the quarterfinals of the Coupe de France after a penalty shootout (5:4). On 4 February, he scored a hat-trick in a 5:2 victory against
Angers SCO. On 17 February, he scored two goals for Marseille in a
Europa Conference League match against
Qarabağ FK. By achieving this, he became the second Marseille player in the 21st century to score at least six goals in
UEFA competitions after
Didier Drogba who scored 11 goals during the
2003–04 UEFA Cup.
Juventus On 26 August 2022,
Juventus announced the signing of Milik on loan from
Marseille for the
2022–23 season. He became the third Polish footballer to play for the club, after
Zbigniew Boniek and
Wojciech Szczęsny. On 31 August, he scored his first goal for Juventus in a 2–0 victory over
Spezia. On 21 June 2023, Juventus signed Milik from Marseille on permanent basis. On 11 January 2024, he scored a hat-trick in a 4–0 victory over
Frosinone helping Juventus advance to its fifth consecutive
Coppa Italia semifinal. On 23 April 2024, he scored the winning goal in a 2–1 loss (2–3 agg.) over
Lazio securing his side the spot in the Coppa Italia final. He missed the entire 2024–25 season after undergoing meniscus surgery in June 2024. ==International career==