Japan competed at the 2014 Summer Youth Olympics, in Nanjing, China from 16 August to 28 August 2014.
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Japan qualified a two archers from its performance at the 2013 World Archery Youth Championships.
Japan qualified 13 athletes.
<small>Qualification Legend: Q=Final A (medal); qB=Final B (non-medal); qC=Final C (non-medal); qD=Final D (non-medal); qE=Final E (non-medal)</small>
Japan qualified two athletes based on the 2 May 2014 BWF Junior World Rankings.
Japan qualified three boxers based on its performance at the 2014 AIBA Youth World Championships
Japan qualified one boat based on its performance at the 2013 World Junior Canoe Sprint and Slalom Championships.
Japan qualified a boys' and girls' team based on its ranking issued by the UCI.
Japan qualified a rider.
Japan qualified three athletes based on its performance at the 2014 FIE Cadet World Championships.
Japan qualified a girls' team based on its performance at the 2013 Under 16 Asian Cup.
Japan qualified one team of two athletes based on the 8 June 2014 IGF Combined World Amateur Golf Rankings.
Japan qualified two athletes based on its performance at the 2014 Asian Artistic Gymnastics Championships.
Japan qualified one athlete based on its performance at the 2014 Asian Rhythmic Championships.
Japan qualified one athlete based on its performance at the 2014 Asian Trampoline Championships.
Japan qualified two athletes based on its performance at the 2013 Cadet World Judo Championships.
Japan qualified one boat based on its performance at the Asian Qualification Regatta.
<small>Qualification Legend: FA=Final A (medal); FB=Final B (non-medal); FC=Final C (non-medal); FD=Final D (non-medal); SA/B=Semifinals A/B; SC/D=Semifinals C/D; R=Repechage</small>
Japan qualified a boys' team based on its performance at the 2013 Rugby World Cup Sevens.
Japan qualified two boats based on its performance at the Techno 293 Asian Continental Qualifiers.
Japan was given a wild card to compete.
Japan qualified eight swimmers.
Japan qualified a girl based on its performance at the 2014 World Qualification Event and a boy based on the Under-18 World Rankings.
<small>Qualification Legend: Q=Main Bracket (medal); qB=Consolation Bracket (non-medal)</small>
Japan qualified two athletes based on the 9 June 2014 ITF World Junior Rankings.
Japan qualified two athletes based on its performance at the 2014 Asian Youth Olympic Games Qualifier.
Japan qualified two athletes based on its performance at the 2014 Asian Cadet Championships.