Soil dissolved organic carbon (DOC) and nitrogen (DON), and their composition play key roles in soil carbon sequestration and nutrient cycling. In this paper, DOC, DON and specific ultraviolet absorbance (SUVA at 254 nm, 260 nm, 272 nm and 280 nm, equaling to the measured absorbance divided by the DOC concentration) of dissolved organic matter, as well as soil physical-chemical parameters (soil organic carbon SOC, soil total nitrogen SON, pH value, electrical conductivity and bulk density) were determined in 0-20, 20-40, 40-60 and 60-80cm soil layers of 25 chronosequence larch plantations. The aim of this paper is to explore the temporal-spatial change of DOC, DON, SOC, SON and functional group (aromaticity, apparent molecular size and hydrophobic capacity) parameters, and their influences on soil physical-chemical properties. In the vertical profile, DOC, DON, SOC and SON in surface soil layer were significantly higher than those in the deep soil layers (P<0.05), while no significant differences were found in SUVA₂₅₄, SUVA₂₆₀, SUVA₂₇₂ and SUVA₂₈₀ (P>0.05); During of the development larch plantation, DOC, SOC and SON at the surface soil (0-20cm) linearly increased with larch age (P<0.05), while no significant changes were observed in deep soils. DON, aromaticity, apparent molecular size and hydrophobic capacity of all testified soil layers did not significantly change with larch age (P>0.05). Thus, DOC accumulation at surface 0-20cm soil (7 mg kg^-1 a^-1) should be a part of the SOC accumulation (762 mg kg^-1 a^-1), while no marked temporal changes were observed in both SON, DON and functional groups. Different from the significant space-temporal changes in total and dissolved C and N, composition of functional group relating to aromaticity, apparent molecular size and hydrophobic capacity were not affected by larch age and soil depth (P>0.05). A further regression analysis showed that these functional groups exponentially decreased with DOC and also significantly related to DON in the deep layer. Pearson correlations showed DOC and DON in surface soil positively correlated with SOC, SON and soil electrical conductivity (P<0.05), while no significant relations between SUVA₂₅₄, SUVA₂₆₀, SUVA₂₇₂, SUVA₂₈₀ and soil physical-chemical properties were found in each soil layer. This indicates that quantity, rather than composition of dissolved organic matter could determine soil physical-chemical property, especially in surface soil. Our findings have scientific significance in understanding dynamics processes of soil carbon and nitrogen from the view of soluble components and functional groups during the plantation development.