| Official Name: | Nong Saeng |
| Native Name: | หนองแซง |
| Native Name Lang: | th |
| Settlement Type: | District |
| Subdivision Type: | Country |
| Subdivision Name: | Thailand |
| Subdivision Type1: | Province |
| Subdivision Name1: | Saraburi |
| Subdivision Type2: | Tambon |
| Subdivision Type3: | Muban |
| Seat Type: | Seat |
| Established Title: | District established |
| Population Total: | 15853 |
| Population As Of: | 2019 |
| Population Density Km2: | auto |
| Area Total Km2: | 87.081 |
| Postal Code Type: | Postal code |
| Postal Code: | 18170 |
| Blank Name Sec1: | Geocode |
| Blank Info Sec1: | 1905 |
| Timezone: | ICT |
| Utc Offset: | +7 |
| Coordinates: | 14.4922°N 100.7844°W |
Nong Saeng (Thai: หนองแซง, in Thai pronounced as /nɔ̌ːŋ sɛ̄ːŋ/) is a district (amphoe) of Saraburi province, central Thailand.
Originally, the district was created as a minor district (king amphoe) under Sao Hai district in 1938.[1] It was upgraded to a full district in 1953.[2]
The most people of Nong Saeng migrated from Vientiane. They established their new town near a pond surrounded by saeng trees, so they named their new town Ban Nong Saeng.
Neighboring districts are (from the north clockwise) Sao Hai, Mueang Saraburi, Nong Khae of Saraburi Province, and Phachi and Tha Ruea of Phra Nakhon Si Ayutthaya province.
The district Nong Saeng is subdivided into 9 subdistricts (Tambon), which are further subdivided into 69 administrative villages (Muban).
| No. | Name | Thai | Villages | Pop.[3] | |
|---|---|---|---|---|---|
| 1. | Nong Saeng | Thai: หนองแซง | 8 | 2,072 | |
| 2. | Nong Khwai So | Thai: หนองควายโซ | 9 | 2,246 | |
| 3. | Nong Hua Pho | Thai: หนองหัวโพ | 7 | 1,774 | |
| 4. | Nong Sida | Thai: หนองสีดา | 6 | 963 | |
| 5. | Nong Kop | Thai: หนองกบ | 7 | 1,675 | |
| 6. | Kai Sao | Thai: ไก่เส่า | 10 | 2,409 | |
| 7. | Khok Sa-at | Thai: โคกสะอาด | 7 | 2,083 | |
| 8. | Muang Wan | Thai: ม่วงหวาน | 8 | 1,697 | |
| 9. | Khao Din | Thai: เขาดิน | 7 | 934 |
There is one subdistrict municipality (Thesaban Tambon) in the district:
There are 5 subdistrict administrative organizations (SAO) in the district: