Martin Klein (12 September 1884 – 11 February 1947) was an Estonian wrestler who competed for the Russian Empire at the 1912 Summer Olympics.

[1] He won the silver medal in the middleweight class, becoming the first Olympic medalist born in the territory of modern Estonia.

He left home aged 17 to work as a sailor, but after two years, together with his brother, signed up to a factory in Saint Petersburg, which was then the capital of the Russian Empire.

Seeking additional income, he became a night-shift guardian in a wrestling club and, in this way, was introduced to the sport.

Since 1962, an international Martin Klein Memorial in Greco-Roman wrestling has been held in Viljandi, Estonia.