Duoxu (/do³³-ɕu³³-na³¹/, Duōxù 多续 or Duōxū 多须 in Mandarin Chinese) is a little-known and virtually undescribed Tibeto-Burman language, spoken in Mianning county (冕宁县), which is located in the Liangshan Yi Autonomous Prefecture (凉山彝族自治州) in Sichuan province (四川省) in the People’s Republic of China. Together with Lizu and Ersu, two closely related languages, Duoxu is currently classified as a member of the Qiangic subgroup of the Tibeto-Burman language family. Duoxu is critically endangered. It is spoken by no more than a few members of the oldest generation, who do not use the language on a regular basis and who, for that reason, have a relatively limited knowledge of it. A survey of all remaining Duoxu speakers in April 2013, conducted by Katia Chirkova, Yuan Xiaowen, and Han Zhengkang, and supported by the Endangered Languages Documentation Programme, identified nine last speakers. All are in their 70s and 80s and bilingual in the local variety of Southwest Mandarin, which is their dominant daily language. None of the speakers has regular conversation partners in Duoxu. These circumstances qualify the remaining Duoxu speakers as ‘semi-speakers’. The present collection is based on interviews with two Duoxu language consultants: Mr. Wu Rongfu (伍荣富) and Mrs. Wu Decai (吴德才), conducted between 2013 and 2016. It includes personal narratives, traditional Duoxu stories, elicitations from Mandarin Chinese, and conversations between these two speakers. The majority of the audio and video recordings in this collection are accompanied by annotations including the following layers of analysis: (1) phonetic transcription (IPA); (2) underlying morpheme sequence; (3) morpheme-by-morpheme gloss; (4) free translation in Mandarin Chinese.