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目的 鉴定上海市南汇区的鼠类, 并探讨大鼠属和小鼠属部分种类的进化关系.方法 使用鼠笼法和夹夜法, 于2014年5月—2015年4月在上海市南汇区捕获鼠类, 扩增鼠类的细胞色素c氧化酶亚基Ⅰ (COⅠ) 、16S r RNA序列片段, 确定鼠种, 并运用邻接法 (Neighbor-Joining, NJ) 和贝叶斯法 (Bayesian Inference, BI) 构建发育树.结果 经比对, 上海市南汇区的38只鼠类分别为褐家鼠 (Rattus norvegicus) 30只和小家鼠 (Mus musculus) 8只, 共2种.序列组成分析显示, COⅠ和16S r RNA片段变异率分别为34.5％和27.7％;两者的碱基转换均大于颠换.遗传距离分析显示, COⅠ基因中种内遗传距离和种间遗传距离有重叠区域, 同理, 16S r RNA的种间遗传距离和属间遗传距离也出现重叠区域.发育树显示, 褐家鼠与大足鼠亲缘关系最近, 黄胸鼠与黑家鼠亲缘关系最近.结论 COⅠ和16S r RNA基因均可鉴定大部分鼠种, 仅有少数鼠种不能被区别开.另外, 遗传距离结合进化树拓扑结构能更好地鉴别不同鼠种.“,”Objective To identify rodent species collected in Nanhui district, Shanghai, and to research the evolutionary relationship of some species of Rattus and Mus. Methods The rodents were captured in Nanhui district, Shanghai with cages and night trapping from May 2014 to April 2015. The cytochrome c oxidase subunit Ⅰ (COⅠ) and16 S r RNA gene sequences of rodents were amplified. The species were confirmed by BLAST in Gen Bank, and the evolutionary trees were constructed. Results There were thirty-eight rats had been captured, including two species (R.norvegicus and M. musculus), in Nanhui district, Shanghai. Sequence composition analysis showed the variation rate of COⅠ and 16 S r RNA was 34.5％ and 27.7％, respectively. The base transition of the two genes was greater than the base transversion. Genetic distance analysis showed there was an overlapping region between the intraspecific ge-netic distance and interspecific genetic distance of the CO Ⅰ gene, the same to the interspecific genetic distance and intergenera genetic distance of the 16 S r RNA gene. The genetic relationship between R. norvegicus and R.nitidus was the closest, the same to R. tanezumi and R. rattus based on the evolutionary trees in this study. Conclusion Both COⅠ and 16 S r RNA gene could be applied to identify most rodent species, except a few rodent species. In addition, combining the genetic distance and topology of genetic tree can identify species more optimally.