| Modder River | |
| Native Name: | Modderrivier |
| Pushpin Map: | South Africa Northern Cape#South Africa |
| Coordinates: | -29.03°N 24.6264°W |
| Subdivision Type: | Country |
| Subdivision Name: | South Africa |
| Subdivision Type1: | Province |
| Subdivision Name1: | Northern Cape |
| Subdivision Type2: | District |
| Subdivision Name2: | Frances Baard |
| Subdivision Type3: | Municipality |
| Subdivision Name3: | Sol Plaatjie |
| Subdivision Type4: | Main Place |
| Established Title: | Established |
| Leader Title: | Councillor |
| Population Footnotes: | [1] |
| Population Total: | 926 |
| Population Density Km2: | auto |
| Demographics1 Title1: | Black African |
| Demographics1 Title2: | Coloured |
| Demographics1 Title3: | Indian/Asian |
| Demographics1 Title4: | White |
| Demographics1 Title5: | Other |
| Timezone1: | SAST |
| Utc Offset1: | +2 |
| Postal Code Type: | Postal code (street) |
| Postal2 Code Type: | PO box |
| Postal2 Code: | 8700 |
| Area Code Type: | Area code |
Modder River (Afrikaans: Modderrivier; "modder" is Afrikaans for "mud") is an irrigation and stock farming town situated south of Kimberley near the confluence of the Riet and Modder rivers in the Northern Cape province of South Africa.
The Second Boer War Battle of Modder River took place here.[2]