He was a member of the Italian Squad at the 1995 Rugby World Cup finals, but his first match was only at 14 October 1995, in a 34-22 loss to France. He played at both the 1999 Rugby World Cup finals and the 2003 Rugby World Cup finals. His only presence at Six Nations was in 2002. Mazzariol greatest international success was the win at European Nations Cup in 1997.