The 2018–19 Czech First League, known as the Fortuna liga for sponsorship reasons, was the 26th season of the Czech Republic's top-tier football league. The defending champions were Viktoria Plzeň, who won their fifth Czech title the previous season. The season was the first with a new league structure in which 16 clubs play each other home and away, until the league is split up into championship, Europa League and relegation groups. Dukla Prague lost seven consecutive games at the start of the season, becoming the first team in the Czech First League to do so.