 He made his debut in a friendly against Algeria on 10 October 1984.He scored the first of his 16 international goals on 6 February 1985 in another friendly, a 3–2 win over Ecuador.Thom played in six of East Germany's qualifiers for the 1986 FIFA World Cup, and scored his first two competitive goals for his country on 28 September 1985 in a 2–1 win over Yugoslavia in Belgrade.