| Municipality of Trebnje | |
| Native Name: | Občina Trebnje |
| Native Name Lang: | sl |
| Settlement Type: | Municipality |
| Coordinates: | 45.9°N 16°W |
| Subdivision Type: | Country |
| Subdivision Name: |  Slovenia |
| Leader Title: | Mayor |
| Leader Name: | Mateja Povhe |
| Unit Pref: | Metric |
| Area Total Km2: | 195 |
| Population Footnotes: | [1] |
| Population Total: | 14641 |
| Population As Of: | 2010 |
| Population Density Km2: | auto |
| Timezone1: | CET |
| Utc Offset1: | +01 |
| Timezone1 Dst: | CEST |
| Utc Offset1 Dst: | +02 |
The Municipality of Trebnje (in Slovenian pronounced as /ˈtɾeːbnjɛ/; Slovenian: Občina Trebnje) is a municipality in Slovenia in the traditional region of Lower Carniola. The seat of the municipality is the town of Trebnje.[2]
The municipality was established on 3 October 1994. It was increased in size on 6 August 1998, when the settlements of Kostanjevica and Ravne nad Šentrupertom were transferred to the municipality from the neighboring Municipality of Litija. It was then reduced in size on 13 June 2006 with the formation of the new municipalities of Mokronog-Trebelno and Šentrupert from the municipality's territory.[3] On February 26, 2011, Trebnje was again reduced in size when the Municipality of Mirna was reestablished.[4]
In addition to the municipal seat of Trebnje, the municipality also includes the following settlements: