The Olympic Council of Ireland confirmed reports Saturday that an athlete made a €3,900 profit ($4,800) on the wagers, and withdrew €3,600 ($4,435) in cash from an account with a gambling operator.
"At the moment, it is between the Olympic Council of Ireland legal department and athlete's counsel," team spokesman Jack McGouran told The Associated Press by telephone.
The athlete's name and sport will not be disclosed during the legal process, the team official said. The details also were not identified in a report Saturday in the Irish Independent daily.
The Irish team, which has 66 athletes registered at the London Games, is handling the case while the International Olympic Committee is "monitoring the situation," McGouran said.
"We are aware of it, we are gathering information and will take action if needed," said IOC communications director Mark Adams.
IOC rules bar athletes from betting on Olympic events.
"We have a proper process of dealing with betting cases which is much more robust than we had before," Adams told reporters, adding that the case appears to have "no effect so far on the games. At the moment it's just to gather the information to decide if there's a case to answer from our side."
Illegal and insider betting in sports has fueled fears that match-fixing and corruption present a bigger threat to the integrity of sports than doping.
The IOC has led efforts in recent years to bring sports federations, law enforcement agencies, governments and the legal gambling operators together to co-ordinate and fund the fight against betting corruption.