目的:研究中国地区发热伴血小板减少综合征病毒(severe fever with thrombocytopenia syndrome virus, SFTSV)分离株已上传至GenBank序列中M片段基本特征及该病毒的遗传和进化规律。方法:从GenBank中获取2020年6月25日前分离于中国的SFTSV毒株M片段全序，利用BioEdit软件进行多序列比对，MEGA5.0软件构建系统发生树，比较不同型别及不同来源SFTSV核苷酸和氨基酸的同源性。结果:在GenBank数据库收集到203株中国地区发热伴血小板减少综合征病毒分离株的M片段全序，其中分离于人的毒株185株，占总毒株的91.1%，分离于蜱的毒株共11株，占总毒株的5.4%，分离于其他动物如羊、鼠、刺猬的共5株，占总毒株的3.5%。系统发生树分析显示中国地区流行优势株为C2基因亚型，占总毒株的42.4%，核苷酸序列和氨基酸序列同源性分别为96.4%～100.0%和94 .5%～100.0%。人源毒株与动物分离株同源性极高，核苷酸序列和氨基酸序列同源性分别为92.5%～100.0%和92.0%～100.0%。结论:对分离自中国的发热伴血小板减少综合征病毒分离株优势株为C2型，且存在着多种型别的共循环。SFTSV可能有从C型向J型进行适应性转换的可能。“,”Objective:To study the basic characteristics and gene evolution of M segment of fever and thrombocytopenia syndrome virus (SFTSV)in China.Methods:The full sequence of M fragment of SFTSV strain isolated in China before June 25, 2020 was obtained from GenBank. The BioEdit software was used for multi-sequence alignment and MEGA5.0 software was used to construct the phylogenetic tree to compare the homology of SFTSV, which came from different types and sources.Results:M fragments of 203 SFTSV isolated in China was collected from GenBank database.. Among them, 185 strains were isolated from humans (91.1%), 11 strains were isolated from ticks(5.4%), and 5 strains were isolated from goat, mice and hedgehog (3.5%). Phylogenetic tree analysis showed that C2 genotype was dominant in China, accounting for 42.4% of total. The nucleotide sequence and amino acid sequence homology were 96.4%~100.0%, 94.5%~100.0%, respectively. The homology of human and animal isolates was very high. The nucleotide sequence and amino acid sequence homology were 92.5%~100.0% and 92.0%~100.0%, respectively.Conclusions:Phylogenetic tree analysis of SFTSV isolates in China based on the M fragment showed that C2 genotype was dominant, and there are multiple types of co-circulation. By comparing M and S-segment-based phylogenetic tree, it suggests that SFTSV may potential undergo adaptive conversion from C-type to J-type.