27 year old Spanish national Angel Carromero was sentenced to four years in jail for a car crash that led to the death of high-profile dissident Oswaldo Paya.
Another Cuban activist, Harold Cepero also died in the crash .
Mr Carromero who was head of the youth wing of Spain's ruling Popular Party and a Swedish activist were injured when the car he was driving hit a tree and crashed on 22 July.
Mr Paya and Mr Cepero had been sitting in the back.
During the trial he denied claims he had been speeding.
Prosecutors were reportedly seeking a seven-year term for vehicular manslaughter.