Temperate forests, as a dominant terrestrial ecosystem, play a pivotal role in global carbon sequestration and climate change mitigation. Previous studies have elucidated the changes of soil organic C (SOC) and its active fractions in bulk soil, but paid little attention to particulate organic C (POC) and mineral-associated organic C (MOC) within aggregates in different forest types, especially in temperate transition area. Here, we collected top (0—20cm) mineral soil from four typical temperate natural forests i.e., Betula platyphylla forest (BP), Picea wilsonii+Larix principis-rupprechtii+Betula.app mixed conifer-broad leaf forest (PLB), P. meyeri+P. wilsonii mixed conifer forest (PP) and L. principis-rupprechtii forest (LP) in the Pangquangou National Nature Reserve, Shanxi Province, China. Physicochemical properties were investigated in soil from these forest types for analyzing the relationship with SOC physical fractions (POC and MOC). We founded that: (1) Forest type significantly affected the content of SOC and total nitrogen (TN) with the highest in the PP (65.31 and 3.65 g/kg, respectively) and lowest in the LP (38.61 and 1.79 g/kg, respectively), but the response of the total phosphorus (TP), ammonium nitrogen (AN) and nitrate nitrogen (NN) to forest types was not obvious. (2) Forest type significantly affected the content of POC, but did not affected the content of MOC, indicating that POC exhibited higher sensitivity to forest type shifts compared to MOC. In addition, MOC and POC contents were respectively as follows the order PP>PLB>BP>LP. We only found that POC content in the LP was considerably inferior to that of the PP (P < 0.05), with no obvious differences among the other forest types. Similarly, the MOC content was the highest in the PP, whereas we observed no significant differences among the four forest types. (3) The ratios of POC/SOC, MOC/SOC, and POC/MOC were unaffected by forest type change. POC/SOC and POC/MOC ratios followed the order LP>BP>PLB>PP, ranging from 21.48% to 28.95% and 29.01% to 43.89%, respectively. MOC/SOC decreased in the order LP (74.38%)>PLB (69.27%)>PP (66.32%)>BP (65.75%), indicating that MOC was the dominant fraction of SOC. (4) Random forest analysis showed that the TN, NN and TP contents significantly impacted POC content from the temperate forest soil, while MOC content was mainly affected by BD, TN and NN contents. Moreover, Redundancy analysis (RDA) revealed that TN and NN were the main factors that controlled SOC and its physical fraction contents. Taken together these results suggested that MOC played a critical role in regulating SOC, and could accumulate SOC to the higher extents in the mixed forest especially in the needle mixed forest compared to the other pure forests. However, the C stability of coniferous forest was better than other forest types. Our findings emphasized the key role of the interplay between soil nitrogen and phosphorus in predicting POC and MOC and soil C pool in forest soil in the temperate transition zone. Future forest management strategies should consider planting nitrogen-fixing species to enhance soil organic carbon sequestration and mitigate global climate change.