| Dumun | |
| Nativename: | Bai (?) |
| States: | Papua New Guinea |
| Region: | Madang Province |
| Speakers: | 120 |
| Date: | 2000 census |
| Ref: | e23 |
| Familycolor: | Papuan |
| Fam1: | Trans–New Guinea? |
| Fam2: | Madang |
| Fam3: | Yaganon? |
| Map2: | Lang Status 20-CR.svg |
| Iso3: | dui |
| Glotto: | dumu1246 |
| Glottoname: | Dumun |
| Glotto2: | baim1246 |
| Glottoname2: | Bai-Maclay |
Dumun is an endangered Madang language spoken in Madang Province, Papua New Guinea.
Dumun is reported to go by the name Bai, but evidently this is a distinct (though related) language, or at least a variety called Bai recorded by Maclay was distinct.[1] [2]