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目的：应用形态与DNA条形码技术鉴别广西横县两种形态相似、栖息生境相同的豆螺——硬豆螺（Bithynia ro?busta）与赤豆螺（Bithynia fuchsiana）。方法在广西横县的河流、沟渠和池塘等生境采集赤豆螺和硬豆螺，观察两种豆螺的外部形态并测量其主要参数，比较螺的雄性生殖系统形态。此外，应用基于COI基因的DNA条形码技术进行螺种鉴别，并构建系统树。结果共采获两种豆螺29个，包括19个赤豆螺和10个硬豆螺。两种豆螺的个体外形基本一致，其壳高、壳宽及形状相近，雄性生殖系统形态相似。COI基因序列变异较小，22条序列共有11个变异位点。经序列的整理和剪切后，22个个体的COI基因片段均为517 bp，无插入、缺失位点。基于COI基因序列构建的系统树表明两类群的个体明显聚为一支。结论根据形态学和COI基因序列证据，采自广西横县的赤豆螺与硬豆螺可能为同种异名。“,”Objective To distinguish two Bithynia species,Bithynia fuchsiana and Bithynia robusta collected from Heng County,Guangxi Zhuang Autonomous Region,by using morphological and DNA barcoding methods. Methods The adult B. fuchsiana and B. robusta were collected from the biotope such as rivers,ditches and ponds in Heng County of Guangxi Zhuang Autonomous Region,China. The two species specimens were identified by measuring shell morphological parameters,compar?ing the characters of the male reproductive system,and using the COI gene barcoding technique and building phylogenetic tree. Results B. fuchsiana and B. robusta were similar morphologically in the shell appearance;they had the similar snail height, snail width,shape and male reproductive structure. The DNA sequence analysis showed that the COI gene of the two Bithynia species had low sequence divergence with 11 variation sites among 22 sequences. The length of the COI gene segment was 517 bp and no insertion sites and deletion loci after sequence edited. All individuals of the two species gathered to one clade in the phylogenetic tree based on COI gene. Conclusion According to the evidence of morphology and COI gene coding sequence,B. fuchsiana and B. robusta from Heng County,Guangxi Zhuang Autonomous Region,are likely to be the same species.