Dissolved organic matter (DOM) is the most active component in soil organic matter, affecting heavy metal’s migration and transformation. Studying their correlation is of great value for environmental monitoring and pollution assessment. In this study, the topsoil (0~30 cm) was collected from the typical coniferous and broad-leaved mixed forest in Heilongjiang Province Maolan’gou National Nature Reserve, located in Xiaoxing’anling, China, and three-dimensional fluorescence spectroscopy- parallel factor analysis method was used to reveal the characteristics of forest soil DOM fluorescence spectra, and further to analyze the correlation between DOM fluorescence component and heavy metal content. The results showed that the forest soil DOM fluorescence index ranged from 1.468 to 1.635, with an average value of 1.531, indicating the DOM source had both autogenic and exogenous characteristics. The biological index ranged from 0.563 to 0.646, with an average value of 0.603, indicating a low contribution rate of recent autogenic source; The humification index ranged from 4.607 to 8.993, with an average value of 6.491, indicating a low degree of humification. Threetypes of fivekinds of fluorescent components were identified from the forest soil DOM fluorescence spectrum, including humus-likesubstances ［ultraviolet fulvic acid-like component (C1) and visible fulvic acid-like component (C2)］, humic acid-like substance (humic acid component, C3), and proteinlike substance ［tryptophanlike component(C4) and tyrosinelike component (C5)］. Humus-like substances accounted for the largest proportion of total components (60.12%), significantly higher than humic acid-like and protein-like substances, while humic acid-like substances accounted for the smallest proportion (11.25%) of total components. C1, C2, and C3 had a significant positive correlation, while C5 was significantly negatively correlated with the other four fluorescent components. There was a significant correlation between the fivekinds of fluorescent components and the fluorescence index, respectively, with only C5 showing a positive correlation with the fluorescence index.The forest soil heavy metal contentswere significant differences in the spatial distribution, with significant positive correlations between As and Cr, Cu and Zn, Ni and Zn, Hg and Pb, and significant negative correlations between Hg and Cu, Ni and Zn, Cr, and Pb, respectively.The correlationsamong the three types of fluorescent substances, Cr and Pb, were not significant, but all fluorescent substances had a significant correlation with Zn. Moreover, there was a significant correlation between humus-like substances and Cu and Hg; humic acid-like substances and Cu, Hg, and Ni; protein-like substances and Ni, respectively.The results of this study provide basic data for monitoring the forest soil environment of Maolan’gou National Nature Reserve and provide references for the assessment of heavy metal pollution in the soil of typical coniferous and broad-leaved mixed forests in Xiaoxing’anling.