An oxygen generating composition capable of uniformly spreading oxygen into water even when the content of calcium peroxide is small and maintaining a stable water environment without clouding, and a method for producing the same. 2 to 20% by weight of calcium peroxide, from 2 to 30% by weight of calcium carbonate, calcium hydroxide and 2 to 30% by weight of phosphoric acid it is made into a shaped body containing a hydrogen phosphate 30-80% by weight and a specific surface area of the outer shape of the molded product 500 × 10 - 6 ~3000 × 10 -6 m 2, and, also, the aspect ratio is 1.0 to 4.5 in the oxygen generating composition and a method of manufacturing the same.과산화칼슘 함유량이 소량이어도, 물 속으로 산소를 고르게 퍼지게 하여, 백탁이 생기지 않고 안정적인 수질 환경을 유지할 수 있는 산소 발생 조성물, 및 그 제조방법을 제공하는 것.과산화칼슘 2∼20 중량%、탄산칼슘 2∼30 중량%、수산화칼슘 2∼30 중량% 및 인산이수소칼슘 30∼80 중량%를 함유하는 성형체로 이루어지고, 성형체의 외형의 표면적이 500×10-6∼3000×10-6m2이며, 또한, 애스펙트비가 1.0∼4.5인, 산소 발생 조성물 및 그 제조방법이다.
