The Beneš-Mráz Be-50 Beta-Minor was a light airplane manufactured in Czechoslovakia shortly before World War II.

First flown in 1935, it was a low-wing cantilever monoplane of wooden construction, with tandem open cockpits and fixed tailwheel undercarriage.

In 1937, the designers created a modernised version, the Be-51, which featured a reduced wingspan and fully enclosed cockpits.

A final variant, the Be-52 Beta-Major retained the Be-50's open cockpits but featured improved aerodynamics and a more powerful Walter Major engine.

Like other Czechoslovakian aircraft, all available machines were impressed into Air Force service at the outbreak of war.