He was 98.
Brazda had served two prison sentences for "debauchery between men" and was among 10,000 people the Nazis interned for homosexuality, Radio France Internationale reported.
The Nazis, who sentenced Brazda as a repeat offender, said homosexuality was a disease that threatened the perpetuation of the German nation.
He was forced to wear a pink triangle, as were other gays.
Brazda, a Czech who spoke German, was born in Saxony and was deported to Czechoslovakia after serving his first prison sentence. He was arrested again after Germany annexed the Sudetenland in 1938.
He said he survived Buchenwald because of his friendship with a Communist kapo, a prisoner who worked in administrative positions, and "a bit more chance than others."
Brazda became a French national in 1960 but did not disclose why he had been interned until 2008 at the urging of friends after the unveiling of a memorial to the Nazis' gay victims in Berlin.
He had since spoken at several schools about his imprisonment and campaigned for memorials to homosexuals deported to Nazi concentration camps during World War II.
His body is to be cremated and his ashes placed next to a companion who died in 2003.