| Country: | Wales |
| Official Name: | Pencarnisiog |
| Coordinates: | 53.2338°N -4.47°W |
| Cardiff Distance Mi: | 132.9 |
| Cardiff Distance Km: | 213.8 |
| London Distance Mi: | 218.5 |
| London Distance Km: | 351.6 |
| Community Wales: | Llanfaelog |
| Unitary Wales: | Anglesey |
| Constituency Welsh Assembly: | Ynys Môn |
| Constituency Westminster: | Ynys Môn |
| Post Town: | Tŷ Croes |
| Postcode District: | LL63 |
| Os Grid Reference: | SH 3524 7360 |
Pencarnisiog is a village in the community of Llanfaelog, Anglesey, Wales, which is 132.9 miles (213.8 km) from Cardiff and 218.5 miles (351.6 km) from London.[1]
There is a Welsh-medium primary school, Ysgol Gynradd Pencarnisiog, in the village, founded in 1911.[2] As of January 2018, the school had the second highest percentage of pupils (aged 5 and over) who spoke Welsh at home in Wales, at 95.6%.[3] In 2024, 89.8 per cent of pupils spoke Welsh at home.[4]