Head coach Hong Myung-bo, who returned last month to take charge of the national team as the long-term replacement for Jurgen Klinsmann, included the winger in his squad after a run of impressive performances for Gangwon FC.
"I think he has done enough this season to deserve a spot on the national team," Hong told reporters on Monday.
"His body of work for this season speaks for itself, and I think this was the right time to give him this opportunity.
"A lot of people have high expectations of him, and I hope he can do some good things for us here. And it's up to him to keep earning these chances."
Yang has been in blistering form for Gangwon this season, helping the club to top spot in the K League with eight goals.
He signed a five-and-a-half-year deal to join Premier League side Tottenham in July and will move to London in January following the conclusion of the season in Korea, linking up with compatriot Son Heung-min.
Son, who has just started his 10th season with Spurs, will captain the South Korean squad next month as the country attempts to reach an 11th consecutive World Cup finals.
