| Alagapuri | |
| Other Name: | Alagapuri |
| Settlement Type: | Village |
| Pushpin Map: | India Tamil Nadu#India |
| Pushpin Label Position: | left |
| Subdivision Type: | Country |
| Subdivision Name: |  India |
| Subdivision Type1: | State |
| Subdivision Name1: | Tamil Nadu |
| Subdivision Type2: | District |
| Subdivision Name2: | Ariyalur |
| Subdivision Type3: | Taluk |
| Subdivision Name4: | Udayarpalayam taluk |
| Unit Pref: | Metric |
| Population Total: | 5105 |
| Population As Of: | 2001 |
| Population Density Km2: | auto |
| Demographics Type1: | Languages |
| Demographics1 Title1: | Official |
| Demographics1 Info1: | Tamil |
| Timezone1: | IST |
| Utc Offset1: | +5:30 |
| Postal Code Type: | PIN |
| Postal Code: | 608901 |
| Area Code Type: | Telephone code |
| Sex Ratio: | 1011 |
| Literacy: | 56.85 |
Alagapuri is a village in the Udayarpalayam taluk of Ariyalur district, Tamil Nadu, India. It is also Known as alagapuram
As per the 2001 census, Alagapuri had a total population of 5105 with 2539 males and 2566 females.[1]