At club level, Lars Björn played exclusively for Djurgårdens IF . From 1949 to 1966 he entered with his team in Division 1 , the then highest Swedish league. In 1950, 1954, 1955, 1958, 1959, 1960, 1961, 1962 and 1963 he won the Swedish championship with Djurgårdens IF .
International
For Sweden Lars Björn participated in the Winter Olympics in 1952 in Oslo and 1956 in Cortina d'Ampezzo and 1960 in Squaw Valley part. At the 1952 Winter Games, he and his team won the bronze medal. As the best European team, Sweden also became European champions. He was also in his country's squad at the 1953 , 1954 , 1957 and 1958 World Championships . At the world championships in 1954 and 1958 he and his team won the bronze medal, and the gold medal at the world championships in 1953 and 1957. At the world championships in 1953 and 1957 he was also European champion with Sweden.