Provided is an oxygen supply device for high altitude jumps. A gas outlet of a gas storage device is connected with an air inlet of a pressure reducing valve set; an air outlet of the pressure reducing valve set is connected with an oxygen inlet of an oxygen regulator; an air supply outlet of the oxygen regulator is connected with an oxygen mask; an oxygen filling valve is arranged at one end of a main body of the pressure reducing valve set, and an air release valve is arranged at the other end of the main body of the pressure reducing valve set; a pressure reducing valve and a pressure gauge are arranged in the middle of the main body of the pressure reducing valve set; a safety valve is arranged at the position, close to the air outlet, of the main body of the pressure reducing valve set; the oxygen regulator comprises a valve body; the valve body is provided with an oxygen inlet, an oxygen regulation cavity, an air inlet, an air supply outlet, an air cavity, an oxygen inlet channel and an oxygen outlet channel, the air inlet communicates with the air supply outlet through the air cavity, the oxygen inlet communicates with the oxygen regulation cavity through the oxygen inlet channel, and the oxygen regulation cavity communicates with the air cavity through the oxygen outlet channel; an oxygen flow regulation module B is arranged in the oxygen regulation cavity; an air flow regulation module C is arranged at the air inlet. The volume and weight of the oxygen supply device are smaller than those of an existing oxygen supply device with the same oxygen supply time, and the oxygen supply device is less influenced by low temperature, is long in oxygen supply time and meets the use requirements of parachuting personnel for respiration.