Abstract: The invention relates to a self-contained device for generating high-pressure breathing oxygen, of the type comprising an oxygen-generating chemical candle (3), a gastight confinement chamber composed of a body (1) and of a cover (2), in which chamber the candle is housed, means of igniting the candle, means of percussing the igniter and means of filtering the oxygen generated, characterized in that the igniting means consist of a compressed mixture of titanium and boron and in that the filtering means consist of a mixture of lime or soda lime and of molecular sieve and are distributed, on the one hand, packed in around the candle and, on the other hand, in a cartridge having a generated-oxygen outlet cap.Application to the generation of oxygen in the medical or paramedical field, the aeronautics field and the military field.