Ogwumike was named to the USA Basketball U18 team. The USA team was one of eight teams from North, South and Central America, along with the Caribbean, invited to participate in the 2010 FIBA Americas U18 Championship For Women, held at the U.S. Olympic Training Center, in Colorado Springs, Colorado. The team was coached by Jennifer Rizzotti. Ogwumike started all five games and was the leading scorer with 13.2 points per game. She was also the leading rebounder with 7.4 rebounds per game. The USA team won all five games and captured the gold medal.
The usual sequence is for the players on the U18 team to move to the U19 team. However. Ogwumike played so well as a U18 that she was promoted to the World University Games team for the 2011 World University Games held in Shenzhen, China. Chiney was not the only Ogwumike on the team, as her sister, Nneka Ogwumike, was also on the team. Both started every game, with Chiney scoring almost ten points per game. She hit 25 of 37 shot attempts for a team leading 67.6% shooting percentage. She helped the USA win all six games and earn the gold medal.