Composting is one of the effective ways for wheat straw utilization. However, the relevant study on solewheat straw composting is still constrained. Dissolved organic matter (DOM) is widely believed to be the most activeorganic matters during composting, and then it can be seen as an indicator for investigating the composting process of straw materials. In this study, total organic carbon analysis, UV-Vis spectroscopy and EEM-PARAFAC were applied to study the evolutions of abundance, structure and composition of DOM during wheat straw compost. The dissolved organic carbon (DOC) of DOM were decreased by 23%, with a major decrease in an early stage of composting, suggesting DOM was an active portion of organic matters. UV-Vis spectra analysis showed that the absorbance of DOM was significantly decreased after composting, suggesting the degradation of aromatic compounds. DOM present obvious changes of fluorescence peaks in EEM during composting, where the strong protein-like peaks were transformed to the humic-like peaks. It indicated that the composition of DOM was changed. SUVA254 and HIX values of DOM varied dynamically, but both were generally increased with composting. It implied that the aromaticity and humification degree of DOM were transformed to be stronger after composting. These results revealed that the non-humic matters were readly to be degraded, and the relative content of humic matters was elevated, resulting in an increase of aromaticity and humification of DOM during composting. EEM-PARAFAC analysis showed that the relative abundances of protein-like compounds (C3) were decreased by 46%, while the relative abundances of fulvic acid-like (C1) and humic acid-like (C2) substances were increased by 45% and 80%. The composition of DOM had been transformed from C1∶C2∶C3=41∶17∶42 to 53∶27∶20 during composting. The results revealed that the protein-like compounds were dominantly degraded, while humic-like matters were somewhat formed or slowly degraded and transformed to be the dominant one. The correlation analysis showed strong positive correlations between HIX, C1 and C2 (r=0.806~0.853), suggesting that HIX could effective reflect the humic characteristics of compost DOM. The results obtained here are greatly help for better controlling wheat straw composting and improving the number of straw manures.