As a main component of the terrestrial ecosystem, soil microorganisms play an important role in its carbon, nitrogen and phosphorus cycle and energy flow. The alpine forest soil samples were taken in the alpine forest at 3 900 m and then moved to the timberline at 4 000 m, to study with natural gradient experiment the effect of simulated warming on the soil microbial biomass of soil organic layer (OL) and mineral soil layer (ML) in snow-covered season. The results showed that simulated warming increased soil temperature, but did not have a significant impact on soil microbial biomass or its ratio. The variance analysis showed that soil layers significantly impacted soil microbial biomass carbon, nitrogen and phosphorus, MBC/MBN, MBN/MBP (P < 0.05); snow had a significant impact on soil microbial biomass nitrogen and phosphorus, MBC/MBN, MBC/ MBP, MBN/MBP (P < 0.01). The correlation analysis showed that soil microbial biomass carbon, nitrogen and phosphorus had significant correlations with soil moisture and temperature (P < 0.05); soil microbial biomass nitrogen and phosphorus had significant correlations with freeze-thaw cycles (P < 0.01); MBC/MBN, MBN/MBP, MBC/MBP had significant correlations with soil temperature and snow depth (P < 0.01). In the long run, the carbon, nitrogen and phosphorus balance of alpine forest ecosystem will depend on the response of soil microbial biomass and community structure to the climate warming.