nilsson played 57 times for the sweden national football team, and participated in several international tournaments. he played in the 1938 fifa world cup, where sweden finished fourth. he took part in the 1948 london olympics, where sweden celebrated its best international result with a gold medal, defeating yugoslavia 3–1 in the final. two years later he competed in the 1950 fifa world cup where sweden finished third, thus becoming one of only two players to play in world cups before and after world war ii (the other being switzerland's alfred bickel). in the 1950 world cup, nilsson was also elected into the all-star team of the tournament. he won another medal in the 1952 helsinki olympics, where sweden won the bronze after defeating west germany 2–0.