The 2017–18 Big Bash League season or BBL|07 was the seventh season of the KFC Big Bash League, the professional men's Twenty20 domestic cricket competition in Australia. The tournament started on 19 December 2017 and finished on 4 February 2018. Perth Scorchers were the defending champions. The competition was extended to a total of 40 group games for the first time, each team playing ten matches in the group.