Peat soil is rich in organic matter, which is the main reason for its poor engineering properties. The content and compositions of organic matter of peat soil lead to the various physical and mechanical properties of this kind of soil. In order to clarify the influence of organic matter content, a series of laboratory tests are conducted on dozens of groups of amorphous peat soil samples with different organic matter content, and the laws of physics, deformation, strength and permeability with organic matter content are systematically analyzed. In order to compare the difference in engineering properties caused by the different organic matter components, the experimental data of the fiber peat soil from domestic and foreign literatures are collected and compared systematically with the physical and mechanical indexes of the amorphous peat soil. The results show that there is a certain linear relationship between the basic physical and mechanical indexes of the amorphous peat soil and the organic matter conten