Jan Lammers (30 September 1926 – 1 September 2011) was a Dutch sprinter. He competed in the 200 m and 4 × 100 m relay events at the 1948 Summer Olympics and finished in sixth place in the relay. As a teenager Lammers trained in gymnastics and changed to athletics only after World War II. At the 1946 European Athletics Championships he was part of the Dutch 4 × 100 m team (with Jo Zwaan, Gabe Scholten and ) that finished in fourth place. In 1948 he won his first Dutch title, in the 200 m. Two years later, he won two national sprint titles and a bronze medal in the 200 m event at the 1950 European Athletics Championships. He was preparing for the 1952 Summer Olympics, but tore a muscle. The same year he got married, retired from competitions and later worked as a garage keeper.