Canada competed at the 2018 Summer Youth Olympics, in Buenos Aires, Argentina from October 6th to 18th.
The Canadian team consisted of 71 athletes competing in 20 sports and was officially named on September 25, 2018. It was announced on October 4, 2018, that Canada received an additional reallocated spot in boxing, meaning the total team size was 72 athletes (33 men and 39 women).
On October 3, 2018, trampolinist Jérémy Chartier was named as the flag bearer during the opening ceremony.
All nations can qualify only a maximum of one team sport per gender and Canada chose men's field hockey and women's rugby sevens.
The following is the list of number of competitors participating at the Games per sport/discipline.
Medals awarded to participants of mixed-NOC (combined) teams are represented in italics. These medals are not counted towards the individual NOC medal tally.
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Canada qualified one boy.
Canada qualified 15 athletes (five boys and ten girls). This marks Canada's largest track and field team at the Youth Olympics.
Canada qualified one boy based on the Badminton Junior World Rankings.
Canada received a reallocated spot to enter a girls team of two athletes.
Canada received a reallocated spot to enter a boy. Canada later received another reallocated spot to send an additional male athlete.
Canada qualified two dancers based on its performance at the 2018 World Youth Breaking Championship.
Canada qualified three fencers (one male and two female).
Canada qualified a boys' team of nine athletes after a bronze medal finish at the Pan American qualification event in Guadalajara, Mexico in March 2018. The team was officially named on September 12, 2018.
Canada qualified one boy and one girl.
Canada qualified four gymnasts (two boys and two girls). The team was officially named on August 31, 2018.
Canada qualified two gymnasts based on its performance at the 2018 American Junior Championship.
Canada qualified one gymnast based on its performance at the 2018 American Junior Championship.
Canada qualified one gymnasts based on its performance at the 2018 American Junior Championship.
Canada qualified the maximum team size of one boy and one girl. Both athletes have to compete in one weight category higher as their weight category is not represented in the Youth Olympics.
Canada qualified one girls in the women's single sculls after being ranked in the top 8 (among eligible nations) at the 2017 World Championships in Trakai, Lithuania. The rower representing Canada was officially announced on September 10, 2018.
Canada qualified a girls' team of twelve athletes after winning the North American qualification event in Las Vegas in March 2018. Canada's 12 women roster was named on August 29, 2018.
Canada qualified one sport shooter based on its performance at the American Qualification Tournament.
Canada received a reallocated quota to send a girl.
Canada's swimming team of eight athletes (four per gender) was announced on April 9, 2018. Canada qualified a full quota of eight athletes. However, changes were made which removed gold medal favourites Gabe Mastromatteo and Margaret MacNeil, along with Alexander Pratt off the team. They were removed and replaced, because they were not available for the games.
Canada qualified one boy at the qualification event in April 2018 in Tunisia.
Canada qualified one athlete based on its performance at the 2018 American Youth Olympic Games Qualifier.
Canada received two reallocated quota spots (one boy and one girl).