A self-breathing electrochemical oxygenerator includes an outer housing including an upper housing part and a lower housing part. A cavity formed by the upper housing part includes a battery installation cavity, a controller installation cavity and an electrochemical assembly installation cavity. Batteries are installed within the battery installation cavity. A controller is installed within the controller installation cavity. A self-breathing electrochemical pure oxygen generation assembly is installed within the electrochemical assembly installation cavity. An upper housing body of the upper housing part corresponding to the electrochemical assembly installation cavity has air holes. After the external oxygen output pipe is blocked, through timely manual operation, the pressure within the pure oxygen generation assembly is ensured to fall within a normal range, so as to ensure that the pure oxygen generation assembly works normally, thereby ensuring long service life of the oxygenerator.