| Chiemsee | |
| Image Coa: | Wappen von Chiemsee.svg |
| Coordinates: | 47.8667°N 37°W |
| Image Plan: | Chiemsee in RO.svg |
| State: | Bayern |
| Region: | Oberbayern |
| District: | Rosenheim |
| Verwaltungsgemeinschaft: | Breitbrunn am Chiemsee |
| Elevation: | 523 |
| Area: | 2.57 |
| Postal Code: | 83256 |
| Area Code: | 08054 |
| Licence: | RO |
| Gemeindeschlüssel: | 09 1 87 123 |
| Website: | www.vg-breitbrunn.de |
| Mayor: | Armin Krämmer[1] |
| Leader Term: | 2020 - 26 |
| Party: | FW |
Chiemsee is a municipality in the district of Rosenheim in Bavaria in Germany, named after the lake Chiemsee. It is Bavaria's smallest municipality by area and the second smallest (after Balderschwang) by population.
The municipal area comprises not the lake itself but the islands of Herrenchiemsee (Herreninsel) with its Palaces, Frauenchiemsee and the uninhabited Krautinsel. While the island of Herrenchiemsee with 2.38km2 is by far the largest, most of Chiemsee's inhabitants live on 0.15km2 Frauenchiemsee.