A climate change experiment was conducted to examine the effect of simulated elevated atmospheric carbon dioxide (CO_2) and temperature simultaneously on soil basal respiration and microbial community structure and abundance in an open field. Field treatments included the atmospheric CO_2 enrichment (CE), warming of canopy air (WA), interactive CO_2 enrichment and warming (CW) and the ambient control (CK) plots in the experiment platform. The results shown that CE had no effect on soil basal respiration, when soil basal respiration under WA treatment was increased by 51.6% and 38.5% at the heading and ripening stages, respectively. At the tillering stage, no change in the abundance of bacteria or fungi was observed, however abundances of fungi were decreased by 32.1%~50.2% and 32.0%~37.4% at the heading and ripening stages, respectively. The analysis of T-RFLP profiles showed that CE, CW and WA treatment had no obvious effect on fungal and bacterial community structure, but changed the archaeal community structure in a certain extent. Comparing to the control, the diversity of fungi was increased by 7.1%~8.2% during the wheat growth period but decreased by 5.3%~13.5% and 22.1%~33.6% under CW and WA treatments, respectively; CE, CW and WA treatment increased bacterial diversity in wheat tillering and heading stages.