Accused of masterminding the massacres of 800,000 people, during the 1994 genocide.
Bagosora was serving a 35-year prison sentence after the International Criminal Tribunal for Rwanda convicted him of crimes against humanity.
The International Criminal Court had sentenced him to life imprisonment, but the sentence was reduced to 35 years.
Bagosora died at the age of 80 and was seriously ill from heart problems.
Bagosora was taken to hospital several times, underwent three surgeries, and died in a sanatorium.
Prosecutors accused Bagosora; who at the time was in charge of the Ministry of Defense, taking charge of the military and political affairs of Rwanda after the murder of President Juvénal Habyarimana; After his plane was shot down in 1994.
The criminal court, sitting in Tanzania, indicted Bagosora; He was in charge of troops and a Hutu militia that killed about 800,000 minority Tutsis and moderate Hutus in 100 days.