Overall, Ruiz has earned 133 caps and has scored 68 goals for his country. He has played in World Cup qualification campaigns for the FIFA World Cups of 2002, 2006, 2010, 2014, and 2018. He played his first international match on 11 November 1998, a friendly against Mexico, and scored his first goal against El Salvador at the 1999 UNCAF Nations Cup. Ruiz represented Guatemala at the 1999 Pan American Games. In 2000, as the Guatemala national futsal team had begun its development, Ruiz was selected, along with other 11-a-side football players, as part of the squad that competed at the 2000 Futsal World Championship, hosted by Guatemala. He scored one goal in the tournament.