There are great differences in the composition and properties of different commercial organic fertilizers， which determines the different decomposition rules of different commercial organic fertilizers in the soil environment.In this study， elemental analysis， thermogravimetric analysis (TG) and Fourier transform infrared spectroscopy (FTIR) were used to analyze the changes of material composition， functional group composition， element composition and physicochemical properties during the decomposition of organic fertilizers from three kinds of protein sources， including soybean meal (SM)， bone meal (BM)， shrimp peptide (SP).After 12 months of decomposition， the pH value， CEC and ash content of the three kinds of organic fertilizer increased significantly， and the HA/FA of SM， BM and SP organic fertilizer increased to 1.87，1.47 and 3.69 times， respectively， and the humification degree was significantly enhanced.The results of TG analysis showed that the protein content of soybean meal organic fertilizer decreased and the polymer carbon complex increased.Except for the carbohydrate of bone meal organic fertilizer shifted to low temperature， the weight loss peaks of three kinds of organic fertilizer shifted to high temperature and the stability increased.The highest mineralization rate of SM was 60.38%， which was 1.65 and 1.6 times higher than that of bone meal and shrimp peptide organic fertilizer， respectively.Except for P and Mg， N， K， Ca， Fe， Mn， Cu and Zn had the highest release rate of SM.FTIR results showed that aliphatic groups， proteins and sugars in the three kinds of organic fertilizers decomposed gradually， and the structure of proteins changed.In the process of decomposition of the three kinds of organic fertilizers， the protein content decreased， the organic carbon content increased， and the stability of organic matter enhanced.SM organic fertilizer has the highest carbon and nitrogen content， mineralization rate and nutrient release rate are higher than BM and SP organic fertilizer.Plant-derived SM organic fertilizer has relatively fast fertilizer effect in farmland.