Eero Lehtonen started athletics as a schoolboy. At the age of 18 he earned his first podium at the Finnish Championships in the pentathlon. In 1920 he was national champion in the pentathlon and long jump, setting a new national long jump record of 7.02. He won the Olympic pentathlon in 1920 and 1924, the last two times it was held. In Antwerpen he also tackled his only decathlon but retired after five events. After the 1920 Olympics Lehtonen briefly retired to concentrate on his professional career, but returned in 1922, again winning the Finnish Championships in long jump and pentathlon. In 1924, he won a third title in the long jump. For Paris he was again well-prepared, beating Hungarian Elemér Somfay and American Bob LeGendre, who had set a world record in the long jump during the pentathlon. Lehtonen ended his career when the pentathlon was dropped from the 1928 Olympic Programme. His hometown of Mikkeli unveiled a bronze statue in his honor in 1984. He was a forester by profession and worked for the state-owned forestry.
Personal Bests: 400 – 53.0 (1924); LJ – 7.02 (1920); Pen – 3416 (1924); Dec – no result.