- Language: Lower Chulym
- Alternate names: Ös? Tadar? Iyus Kizhi?
- Language code: dclwl
- Language family: Turkic, Common Turkic, Central Siberian Turkic, South Siberian Turkic
- Dialect of: Chulym
- Number of speakers: Extinct
Lower Chulym is among the most poorly documented Turkic languages. It has traditionally been described as a dialect of a Chulym language, along with the Middle dialect, or Ös. Although Chulym has no official status, the Middle dialect served as the de facto standard for the two varieties. Middle and Lower Chulym are reported to be mutually unitelligible, and, based on traditional classificatory criteria, belong to separate branches of Turkic.