| Official Name: | Bang Pahan |
| Native Name: | บางปะหัน |
| Native Name Lang: | th |
| Settlement Type: | District |
| Subdivision Type: | Country |
| Subdivision Name: | Thailand |
| Subdivision Type1: | Province |
| Subdivision Name1: | Ayutthaya |
| Subdivision Type2: | Seat |
| Subdivision Name2: | Bang Pahan |
| Subdivision Type3: | Tambon |
| Subdivision Name3: | 17 |
| Subdivision Type4: | Muban |
| Subdivision Name4: | 94 |
| Established Title: | District established |
| Population Total: | 38799 |
| Population As Of: | 2000 |
| Population Density Km2: | 318.3 |
| Area Total Km2: | 121.9 |
| Blank Name Sec1: | Postal code |
| Blank Info Sec1: | 13220 |
| Blank Name Sec2: | Geocode |
| Blank Info Sec2: | 1407 |
| Timezone: | ICT |
| Utc Offset: | +7 |
| Coordinates: | 14.4625°N 100.5447°W |
Bang Pahan (in Thai pronounced as /bāːŋ pā.hǎn/) is a district (amphoe) in the northern part of Ayutthaya province.
The district was originally named Nakhon Luang Nai, but was renamed in 1916 to Bang Pahan as the name of the central tambon.
The Phuan people from Vientiane who migrated around this area in the reign of King Rama II established the settlement. They also built a windmill in their village, thus the village was named Ban Kanghan after the Thai word for windmill (Kanghan, กังหัน). The name was later corrupted by misspellings to Pahan.
Neighboring districts are (from the north clockwise) Maha Rat, Nakhon Luang, Phra Nakhon Si Ayutthaya and Bang Ban of Ayutthaya province, and Pa Mok of Ang Thong province.
The district is divided into 17 sub-districts tambon, which are further subdivided into 94 villages muban. The township (thesaban tambon) of Bang Pahan covers tambon Khwan Mueang and parts of the tambon Bang Pahan and Bang Nang Ra.
| No. | Name | Thai | Villages |
|---|---|---|---|
| 1. | Bang Pahan | บางปะหัน | 7 |
| 2. | Khayai | ขยาย | 6 |
| 3. | Bang Duea | บางเดื่อ | 6 |
| 4. | Sao Thong | เสาธง | 5 |
| 5. | Thang Klang | ทางกลาง | 4 |
| 6. | Bang Phloeng | บางเพลิง | 3 |
| 7. | Hansang | หันสัง | 7 |
| 8. | Bang Nang Ra | บางนางร้า | 5 |
| 9. | Ta Nim | ตานิม | 4 |
| 10. | Thap Nam | ทับน้ำ | 5 |
| 11. | Ban Ma | บ้านม้า | 4 |
| 12. | Khwan Mueang | ขวัญเมือง | 5 |
| 13. | Ban Li | บ้านลี่ | 5 |
| 14. | Pho Sam Ton | โพธิ์สามต้น | 8 |
| 15. | Phutlao | พุทเลา | 12 |
| 16. | Tan En | ตาลเอน | 3 |
| 17. | Ban Khlo | บ้านขล้อ | 5 |