The 2018–19 Biathlon IBU Cup was a multi-race tournament over a season of biathlon, organised by the International Biathlon Union. IBU Cup is the second-rank competition in biathlon after the Biathlon World Cup. The season started on 26 November 2018 in Idre, Sweden and ended on 16 March 2019 in Martell-Val Martello, Italy. The defending overall champions from the 2017–18 Biathlon IBU Cup were Vetle Sjåstad Christiansen from Norway and Karolin Horchler from Germany.