The invention provides a positive pressure type firefighting oxygen respirator. A shell of the positive pressure type firefighting oxygen respirator is a cavity formed by buckled connection of an upper cover and a lower cover, a fixed oxygen bottle is arranged at the bottom of the respirator, a bottle switch is arranged on a bottle opening of the oxygen bottle, and is connected with a pressure reducer through a nut, the pressure reducer is connected with an alarm device, an oxygen meter, a positive pressure spring, an automatic oxygen supply valve and a manual oxygen supply valve through an oxygen pipe, the automatic oxygen supply valve is connected with an oxygen bag through an oxygen pipe, a quantitative supply valve achieves quantitative oxygen supply through quantitative holes, needs of a user are met, the quantitative supply valve and the manual oxygen supply valve are connected with a cooling unit through a pipeline and a three-way valve, the oxygen bag is connected with a clean tank, the cooling unit and a water draining valve through an oxygen pipe, the clean tank and a cooling tank are connected with a comprehensive cover through a respiring pipeline. The positive pressure type firefighting oxygen respirator is firm, resistant to high temperature, free of peculiar smell, comfortable in wear, convenient to maintain, smooth in respiring and high in view rate and safety, and the quality and the effect of the novel positive pressure type firefighting oxygen respirator are greatly improved.