[2][3] Bhutan, South Sudan, Gibraltar and Kosovo made their FIFA World Cup qualification debuts,[4][5][6][7][8] while Myanmar participated after successfully appealing against a ban from the competition, although the team was obliged to play its home matches outside the country.

[9][10] While the main qualifying draw took place at the Konstantinovsky Palace in Strelna, Saint Petersburg, on 25 July 2015,[11][12] qualification matches were played before that.

[16] In October 2013, UEFA President Michel Platini proposed that the World Cup finals should be expanded from 32 to 40 teams starting from 2018.

[17] This was in response to FIFA President Sepp Blatter's comments that Africa and Asia deserved more spots in the World Cup finals at the expense of European and South American teams.

[18] However, FIFA general secretary Jérôme Valcke said that expansion in 2018 would be "unlikely", while Russian sports minister Vitaly Mutko said that the country was "preparing on the basis that 32 teams will be taking part.

[3] Kuwait had a number of their qualifiers cancelled for a similar suspension that began while their campaign was underway,[22] which eventually resulted in their elimination.

Brazil were the first team to achieve qualification for the tournament following their 3–0 victory over Paraguay and Uruguay's loss to Peru on 28 March 2017.

[23] Peru became the 32nd and final team to qualify when, 233 days after Brazil secured their place, they beat New Zealand 2–0 on aggregate in the OFC-CONMEBOL play-off.

[25] The AFC Executive Committee meeting on 16 April 2014 approved the proposal to merge the preliminary qualification rounds of the FIFA World Cup and the AFC Asian Cup, which was expanded to 24 teams starting in 2019:[26] The draw for the third round was held on 12 April 2016 at the Mandarin Oriental Hotel in Kuala Lumpur, Malaysia.

[29] Zimbabwe, even though they entered the competition, were expelled on 12 March 2015 for their failure to pay former coach José Claudinei a severance fee.

[40] A previous proposal adopted by the OFC in October 2014 would have the eight teams divided into two groups of four teams to play home-and-away round-robin matches in the second round, followed by the top two teams of each group advancing to the third round to play in a single group of home-and-away round-robin matches to decide the winners of the 2016 OFC Nations Cup which would qualify to the 2017 FIFA Confederations Cup and advance to the inter-confederation play-offs.

[52][53] The matchups were decided at the preliminary draw which was held on 25 July 2015, at the Konstantinovsky Palace in Strelna, Saint Petersburg, Russia.