Abstract: An experiment carried on chemistry analyze on the watersoluble organic material (WOM) that formed during in the progress of decomposition of corn stalk, tree leaves, chicken manure and cow dung and also carried on the research on the infrared spectroscopy. It was showed that the WOM total amount and the components of different organic fertilizers were different. And the scale of watersoluble humic acid (WHA) was very large of leaves and corn stalk during the decomposition. And the scale of watersoluble little-molecular organic material (WLOM) was very large in the excrement of the chicken manure and cow dung during the decomposition. In the progress of material decomposition, the aliphatic and amide compounds decreased, but the organic acids proportion increased. In WHA, methyl, methylene, methine and aliphatic compounds increased, but amide compounds decreased. The aliphatic chain and saccharide compounds decreased of leaves. On the contrary, which applied with the cows dung increased during the decomposition. Alkali-soluble humic acids (AHA) from chicken manure was lack of aliphatic and saccharide increased. And the AHA from corn stalk was different in period of different decomposition.