Ẹjọ́ Dreyfus (Faransé: l'affaire Dreyfus) je skanda oloselu that divided France in the 1890s and the early 1900s. It involved the conviction for treason in November 1894 of Captain Alfred Dreyfus, a young French artillery officer of Alsatian Jewish descent. Sentenced to life imprisonment for allegedly having communicated French military secrets to the German Embassy in Paris, Dreyfus was sent to the penal colony at Devil's Island in French Guiana and placed in solitary confinement.