| Conventional Long Name: | West Borneo (Special Region) |
| Native Name: | Daerah Istimewa Kalimantan Barat |
| Common Name: | West Borneo |
| Subdivision: | State-level autonomous region |
| Nation: | Indonesia |
| P1: | Dutch East Indies |
| Flag P1: | Flag of the Netherlands.svg |
| S1: | West Kalimantan |
| Flag Type: | Flag |
| Image Map Caption: | Location of West Borneo within the USI |
| Date Start: | 12 May |
| Year Start: | 1947 |
| Date End: | 22 April |
| Year End: | 1950 |
| Life Span: | 1947 – 1950 |
West Borneo Special Region (Indonesian: Daerah Istimewa Kalimantan Barat) was a component entity of the United States of Indonesia in western part of Borneo. It was established on 12 May 1947 with capital at Pontianak. West Borneo was dissolved on 22 April 1950 and became part of Kalimantan Province which was formed on 14 August 1950 with its capital at Banjarmasin. Following the division of Kalimantan Province, the former territory of West Borneo was assigned to West Kalimantan in 1956 where it remains today.