During the 2018–19 season, Ajax participated in the Eredivisie, the KNVB Cup and the UEFA Champions League.

With winning both the competition and the cup, it meant the first double won since the 2001–02 season.

After beating Juventus in the quarter-final, they reached a Champions League semi-final for the first time since 1997.

On an individual level, Dušan Tadić was the biggest surprise; signed from Southampton in June 2018 for just €11.4 million, the 30-year old unexpectedly became the club's leading goalscorer with a total of 38, including 9 goals in the Champions League.

For a list of all Dutch football transfers in the winter window (1 January 2019 to 1 February 2019) please see List of Dutch football transfers winter 2018–19.