Biochar is a kind of carbon-rich solid material prepared out of biomass through pyrolysis in an oxygen-limited environment. Recently, it has been attracting more and more attention. Biochar amendment into soil is thought to be a good approach to carbon sequestration, which may in turn improve soil physical and chemical properties, such as nutrient and water holding capacity, soil fertility and crop yield. However, how biochar affects soil microbe is still a topic that needs further study. Soil microbial communities are sensitive to biochar amendment, and microbial community structure varies significantly with type of biochar. However, little is known about effects of the amendment of biochar together with litter on soil microbial communities in artificial forests in Subtropical China. In this paper, an investigation was conducted of impacts of fir (Cunninghamia lanceolata) litter and its biochar on soil properties and microbial community structure in a fir plantation in the Jianou Wanmulin Nature Reserve of Fujian Province, in the hope of providing some valuable information for rational utilization of the biomass resources and management of carbon sequestration in the artificial forest in Subtropical China. The biochar was prepared out of fir litter through pyrolysis at three different temperatures, 350 °C, 550 °C and 750 °C. Soil samples were collected from the plantation, and prepared into eight treatments by amending fir litter, biochar or both, separately, such as: (1) control soil (S); (2) soil+litter (S+L); (3) soil+350 °C biochar (S+BC350); (4) soil+550 °C biochar (S+BC550); (5) soil+750 °C biochar (S+BC750); (6) soil+litter+350 °C biochar (S+L+BC350); (7) soil+litter+550 °C biochar (S+L+BC550); (8) soil+litter+750 °C biochar (S+L+BC750), and the litter and biochar was added both at a rate of 2% of the dry soil mass. All the soil samples were incubated in the dark at 25 °C for 364 d. At the end of the incubation, the soil samples were analysed for soil properties, using conventional methods and for soil microbial biomass and community structure using the phospholipid fatty acid method. Results show that pH was 9.4%~12.7% and 9.6%~12.7% higher in Treatment S+BC and Treatments S+L+BC (regardless of preparation temperature) than Treatment S and C/N ratio was 27.1%~41.8% and 26.3%~41.8% higher, respectively. And the effect was more significant in Treatment S+L+BC750 than in Treatment S+L+BC350. The amendments, regardless of which, increased soil total carbon by 21.7%~94.6%, and total nitrogen by 16.2%~45.7%, but the effect on total carbon was more significant in Treatment S+BC than in Treatment S+L and in Treatment S+BC350 than in Treatment S+BC750. Phospholipid fatty acid analysis shows that Treatment S+L and Treatments S+L+BC were both significantly higher than Treatment S in total PLFAs, fungi abundance and fungi to bacteria ratio, and Treatments S+BC and Treatments S+L+BC were significantly higher than Treatment S in ratio of gram positive bacteria to gram negative bacteria. However, Treatment S+L and Treatments S+L+BC were lower than Treatment S in abundance of actinomycetes, but Treatments S+L+BC were much higher than Treatment S+L in abundance of actinomycetes. Principal component analysis (PCA) shows that microbial community structure varied significantly with type of the amendment. Canonical correspondence analysis (CCA) shows that the amendments changed soil properties, including soil pH, C/N, total carbon, total nitrogen, dissolved organic carbon (DOC) and dissolved organic nitrogen (DON), which in turn affected the soil microbial community structure. The effects of amendment increasing soil total carbon, C/N and soil pH were more significant in Treatment S+BC than in Treatment S+L, but the effect of increasing soil microbial biomass was more in Treatment S+L than in Treatment S+BC, and so was the effect on soil microbial community structure. Treatments S+L+BC may not only improve soil properties, but also stimulate growth and alter community structure of the soil microbe.