The present invention relates to a method for preparing a naturally fermented composition comprising fixed nitric oxide precursors, and a naturally fermented composition prepared by the same, and more specifically, the present invention may provide a natural substance-based NO-generating preparation which stably contains a large quantity of nitrogen oxide and thus can help maintain a normal NO balance in a human body； is easy to ingest； and does not cause adverse side effects. To this end, the method for preparing a naturally fermented composition comprising fixed nitric oxide precursors according to one embodiment of the present invention comprises: a first fermentation step in which a nitrogen-containing organic material existing in nature, water, and fermentation bacteria are mixed and aerobically fermented at temperatures of 50°；C or below for 10-30 days to disintegrate and convert sugars and proteins in the organic material, thereby increasing the distribution ratio of the fermentation bacteria； a second fermentation step in which supernatant obtained by solid-liquid separation of the fermentation product is aerobically fermented at 20-30°；C for 10-20 days, thereby increasing ammonia generation； and a third fermentation step in which after additionally supplying carbon sources to the fermentation product having undergone the second fermentation step, the fermentation product is aerobically fermented at 20-40°；C for 10-15 days until the sugar content of the fermentation product reaches 0.3 Brix or less, thereby converting and fixing ammonia nitrogen in the supernatant into nitrite, and the residual organic material is disintegrated and converted.COPYRIGHT KIPO 2020본 발명은 고정된 산화질소 전구물질을 함유한 천연발효 조성물의 제조방법 및 이 방법으로 제조된 천연발효 조성물에 관한 것으로, 산화질소의 전구물질을 안정적으로 다량 함유하여 인체 내의 정상적인 NO 밸런스를 유지하는 데 도움을 주며 섭취가 용이하고 부작용이 없는 천연물 기반의 NO 생성 제제를 제공하는 것을 목적으로 한다.이를 위해 본 발명의 일 양상에 따른 고정된 산화질소 전구물질을 함유한 천연발효 조성물의 제조방법은, 자연계에 존재하는 질소함유 유기물질과, 물과, 발효균주를 혼합한 후 50℃ 이하의 온도에서 10~
