There is no unifying conclusion among the considerable studies of soil microbial community composition under different vegetation types. We selected a distinct vertical vegetation distribution belt consisting of broad-leaved forests, coniferous forests, and subalpine meadows to study the effect of vegetation types on soil microbial community composition. Soil samples were collected at three different depths (0-5cm, 5-10cm, 10-20cm) from sites of five vegetation types. These sites were distinguished by their dominating vegetation: poplar (Populus davidiana) (1250-1300m), poplar (P. davidiana) mixed with birth (Betula platyphylla) (1370-1550m), birth (B. platyphylla) (1550-1720m), larch (Larix principis-rupprechtii) (1840-1890m) and subalpine meadow (1890-1951m). Soil microbial community compositions under the various vegetation types were determined by phospholipid fatty acid (PLFA) analysis. Ordination of individual PLFA signatures and correlations among soil properties and soil microbial PLFA indicators were analyzed by principal components analysis (PCA) and redundancy analysis (RDA), respectively. The results indicated that total PLFA contents of soil microbial community, biomasses of four main microbial taxa (fungi (f), bacteria (b), gram-positive bacteria (G+), gram-negative bacteria (G-)), and microbial community structure were significantly affected (P < 0.05) by soil organic carbon (SOC) under all vegetations; PLFA contents of total microbial community and main taxa generally decreased as soil depth increased, while G+/G-and f/b increased with soil depth. Among different vegetations, total PLFA contents and main taxa biomass under mixed broad-leaved forests were the highest; f/b and G+/G-under coniferous forests were higher than those under broad-leaved forests; the availability of SOC under subalpine meadows was constrained on some level by the low pH value, which led to a relatively high f/b and G+/G-. In conclusion, the effect of SOC on soil microbial community composition was the most significant of all soil parameters under all vegetation types, though the availability of SOC could be constrained by relatively low pH values on some level; fungi was more sensitive to the changes of vegetation types while bacteria was more sensitive to the variability of nutrient availability and pH. This conclusion could have a significant impact on forecasting soil microbial community composition under different vegetations.