Ondruš played 58 matches for Czechoslovakia and scored 9 goals. As a captain, he led the national team in the 1976 UEFA European Championship. His superb performance against Cruyff's Netherlands in semi-finals where he scored twice (one own goal) opened his team the door to the final match where Czechoslovakia won the gold medal in the famous Belgrade Night game against the then world champion West Germany. At the 1980 UEFA European Championship, he contributed to the national team's bronze medal.