| Official Name: | Sirindhorn |
| Native Name: | สิรินธร |
| Native Name Lang: | th |
| Settlement Type: | District |
| Subdivision Type: | Country |
| Subdivision Name: | Thailand |
| Subdivision Type1: | Province |
| Subdivision Name1: | Ubon Ratchathani |
| Subdivision Type2: | Seat |
| Subdivision Name2: | Nikhom Sang Ton-eng Lam Dom Noi |
| Subdivision Type3: | Subdistricts |
| Subdivision Name3: | 6 |
| Subdivision Type4: | Mubans |
| Subdivision Name4: | 76 |
| Established Title: | District established |
| Established Date: | 1992 |
| Population Total: | 52981 |
| Population As Of: | 2015 |
| Blank Name Sec1: | Postal code |
| Blank Info Sec1: | 34350 |
| Blank Name Sec2: | Geocode |
| Blank Info Sec2: | 3425 |
| Timezone: | ICT |
| Utc Offset: | +7 |
| Coordinates: | 15.2017°N 105.3983°W |
Sirindhorn (Thai: สิรินธร;) is a district (amphoe) of Ubon Ratchathani province, Thailand, established by the Royal Decree Establishing Amphoe Sirindhorn, BE 2534 (1991), coming into force on 4 January 1992. It was named in the honour of Princess Sirindhorn on the occasion of her 36th birthday.
The district was created effective 3 January 1992 by splitting off tambon Kham Khuean Kaeo from Khong Chiam and the five tambons, Khan Rai, Chong Mek, Nikhom Sang Ton-eng Lam Dom Noi, Non Ko, and Fang Kham, from Phibun Mangsahan.[1]
Neighboring districts are (from the south clockwise): Buntharik, Phibun Mangsahan and Khong Chiam. To the west across the Mekong river is the Lao province of Champasak.
The Sirindhorn Dam that dams the Dom Noi River is in this district. There is a border crossing to Laos here - from Chong Mek on the Thai side to Vang Tao on the Lao side, with onward travel typically to Pakxe.
The district is divided into six subdistricts (tambons), which are further subdivided into 76 administrative villages (mubans).
| No. | Name | Thai | Villages | Pop.[2] | |
|---|---|---|---|---|---|
| 1. | Khan Rai | Thai: คันไร่ | 16 | 11,483 | |
| 2. | Chong Mek | Thai: ช่องเม็ก | 13 | 9,301 | |
| 3. | Non Ko | Thai: โนนก่อ | 14 | 10,613 | |
| 4. | Nikhom Sang Ton-eng Lam Dom Noi | Thai: นิคมสร้างตนเองลำโดมน้อย | 13 | 7,538 | |
| 5. | Fang Kham | Thai: ฝางคำ | 4 | 3,588 | |
| 6. | Kham Khuean Kaeo | Thai: คำเขื่อนแก้ว | 16 | 10,458 |
There are two subdistrict municipalities (thesaban tambons) in the district:
There are five subdistrict administrative organizations (SAO) in the district: