 He made his senior international debut on 28 January 1998, in a 3–0 home win over Slovakia, providing two assists during the match; in his next appearance, in an international friendly against Paraguay on 22 April 1998, he scored his only two goals for Italy, one from a bicycle kick, as they won the match 3–1 at home.Moriero was a participant for Italy at the 1998 FIFA World Cup, under Cesare Maldini once again, where Italy were eliminated in the quarterfinals to hosts and eventual champions France on penalties.Although he was often alternated with the more defensive-minded Angelo Di Livio on the right wing, he still appeared in all five of Italy's matches during the tournament, and he assisted Christian Vieri's first goal in Italy's 3–0 win against Cameroon in their second group stage match, also starting the play for his second goal of the match.