The qualification process was a series of tournaments organised by the five FIVB confederations to decide 22 of the 24 teams which would play in the final tournament, with
Japan qualifying automatically as hosts and
United States also qualifying automatically as the defending champions. All remaining FIVB member associations were eligible to enter the qualifying process. At first, 160 associations registered teams to compete in the qualification process, but 46 associations withdrew from the qualifying process after they registered and
India were suspended and then expelled from taking part in the process as a punishment for internal problems in the India Volleyball Federation. The five regional governing bodies were allocated the remaining 22 spots;
CAVB (Africa) was granted two,
AVC (Asia and Oceania) four,
NORCECA (North America) six,
CSV (South America) two, and
CEV (Europe) eight spots. Of the 24 nations qualified to play at the 2018 World Championship, 21 countries competed at the previous tournament in
2014.
Trinidad and Tobago qualified for the first time. Other teams returning after absences of the last tournament(s) include
Kenya and
South Korea, who both missed the 2014 edition. ==Squads==