[1] Slovan Bratislava were the defending champions, having won the previous season's Cup by defeating Ružomberok in the final by a score of 3–1.
[2] The Cup this season was a knockout tournament contested between 236 clubs.
Matches which were level after regulation advanced to penalties to determine a winner.
[3] Sixty-four matches in the second round were played from 7 August 2018 to 6 September 2018.
[7] Eight matches in the sixth round were played from 23 October 2018 to 16 November 2018.