Global change has been concerned about worldwide since climate change characterized by global warming and atmospheric CO2 enrichment is changing the structure and function of terrestrial ecosystem. Meanwhile, numerous studies undertaken over the past decade have led to the general conclusion that enzymes in mineral soil and soil organic layer play a key role in the soil biochemical process and are closely related to the cycles of bioelements and energy fluxes in forest ecosystem. Therefore, understanding of soil enzyme activity responses to simulated atmospheric CO2 enrichment, elevated temperature and their interactions remain essential for predicting the changes in the high-frigid forest ecosystem function and structure in the future. Little is known about the responses of the activities of soil enzymes that are related to the cycles of carbon, nitrogen and phosphorus to simulated climate change, although numerous reports have been published on the responses of the forest structure and function to free atmospheric CO₂ enrichment. Therefore, 72 intact soil columns from the primary fir (Abies faxoniana Rehder & E. H. Wilson) forest were parked in the controlled environmental chamber, and the activities of invertase, urease, nitrate reductase and acid phosphatase, which are related to the cycles of organic carbon, nitrogen and phosphorus in mineral soil and organic layer under simulated atmospheric CO₂ concentration increase ((350±25) μmol•mol-1) (EC), elevated temperature (2.0℃±0.5℃) (ET) and their interaction (ECT) were measured simultaneously to understand the monthly variations on enzyme activities and their responses to climate change in the future. The significant monthly variations on the activities of the studied enzymes were observed in soil organic layer and mineral soil with the highest enzyme activities in summer, implying that monthly variation of soil temperature was a main factor to regulate the monthly patterns of soil enzyme activities in the subalpine forest. The highest activities were observed in June for invertase in soil organic layer, in July for invertase in mineral soil and urease and acid phosphatase in organic layer and mineral soil, and in August for nitrate reductase in organic layer and mineral soil. The different monthly patterns of enzyme activities are attributed to enzyme sources and soil layer. The monthly dynamics on enzyme activities were of ecological significance for soil nutrient availability and tree nutrition in the subalpine forest ecosystem. EC had influenced slightly on the activities of the studied enzymes in organic layer and mineral soil resulting from the higher CO₂ concentration in soil atmosphere where was higher than 50000 μmol•mol-1 and no direct effect owing to no trees planted on soils. ET increased the activities of the studied enzymes in organic layer and mineral soil significantly comparing with the control (CK) since the elevated temperature was beneficial to microbial growth and propagation. The increments of the enzyme activities in organic layer were higher than those in mineral soil, implying that soil organic layer was more sensitive to climate change. ECT sharply increased the activities of the studied enzymes in organic layer and mineral soil comparing with the EC and CK treatments, but there was no significant difference between the ET and ECT, which was also attributed to no indirect effect by elevated atmospheric CO₂ concentration owing to no trees planted on soils, implying that the increment of the enzyme activities resulted from the temperature effect. However, there was lack of researches on indirect effect and complex effect on soil enzyme activity caused by elevated atmospheric CO₂ concentration, temperature and their interactions, which limited the understanding of soil enzyme responses to climate change. More attentions should be paid to direct, indirect and interactive effects on soil enzyme activities in the future.