Jenna O'Hea first wore the green and gold in 2004 and in the same year won the U/19 Oceania Championship and the WNBL's Rookie of the Year award. She went on to win the 2006 U/21 Oceania Championship and finished with silver at the 2007 Young Women's World Championships. O’Hea made her debut for the senior national team in 2009 and played at the 2010 World Championships where Australia finished fifth. Having spent time playing in France and in America with WNBA team the L.A. Sparks, O’Hea earned her spot on the London Olympic team.
Making her Olympic debut at the London Games, O’Hea and the Australians finished second in their pool after a costly 74-70 overtime loss to France. The Opals defeated China in the quarter-final (75-60) and then faced the USA earlier than expected for a berth in the gold medal match.
Despite going down to the Americans 86-73, O’Hea and the Opals bounced back in the bronze medal match against Russia to take the win 83-74. Winning a bronze medal on debut, O’Hea led the Australians in assists in the tournament with 3.5 per game while adding 7.4 points in an average game time of just over 23 minutes.