The 2017–18 Liga II (also known as 2017–18 Liga II Casa Pariurilor) was the 78th season of the Liga II, the second tier of the Romanian football league system. The season began on 5 August 2017 and ended on 2 June 2018. A total of 20 teams contested the league. It was the second Liga II season with a single series. The season was played in a round-robin tournament. The first two teams promoted to Liga I at the end of the season and the third-placed team played a play-off match against the 12th-placed team from Liga I. The last five teams relegated to Liga III.