Johan Bertil Karl von Wachenfeldt (4 March 1909 – 30 September 1995) was a Swedish sprinter who specialized in the 400 m distance. He competed in the 4 × 400 m relay at the 1928 and 1936 Summer Olympics and finished in fourth and fifth place, respectively; in 1936 he failed to reach the final of the individual 400 m event. Wachenfeldt won three bronze medals at the European championships: two in 1934 and one in 1938. He won the national 400 m title in 1935 and 1938 and held the national records over 300 m and 400 m.