Johann Lahr (21 January 1913 – 24 February 1942) was a Czechoslovak ski jumper. He competed in the individual event at the 1936 Winter Olympics. On 2 March 1941, he set personal best at 111 m (364 ft) in Planica, and not a world record as it was misconception for many years. Lahr, an ethnic German, served in Wehrmacht, and was killed in action on the Eastern Front during World War II.