Abstract: The spiral ultra—microfossils have been discovered in the pelagic knobbly manganese nodules from the East Pacific Ocean (Photo 1) with the help of transmission electron microscope JEM 200CX. It has been revealed that the chain-like and the spiral ultra-microbes are the real builders of the stromatolite (admirabilis), i.e. the coatings of manganese nodules (Photo 2). The colony of the spiral microbes are of disk-like or irregular morphology with a sunken center (Photo 3). The nutritive hypha and the reproductive hypha can be discriminated based on their morphology (Fig.1). The branching nutritive hypha grow from the center of colony to its periphery and the width of the hypha bundles is about 17-60nm. The spiral reproductive hypha about 2-4nm in diameter (Photo 4，5，Fig.2). The screws formed by the spiral reproductive hypha are 3-25nm wide and 35-200nm long. The spheroidal sporangium of 9-50nm in diameter can be seen among the mycelium (Photo 6). The spheroidal spores of 4-6nm diameter can be found in these case. The authors propose setting up a new species Spirisosphaerospora pacifica in the Actinomyes. The discovery of the ultra-microfossils has produced a direct evidence in support of biogenec formation of the manganese nodules. Some peculiar feature of the pelagic manganese nodules such as heterogeneity in mineral composition, poor crystallinity, special structure and texture, can be explained reasonably by the biogenic formation. The new ultra-microfossils as a large molecule will promote the research work on the origin and evolution of life.