| Official Name: | Asteasu |
| Pushpin Map: | Spain |
| Pushpin Map Caption: | Location in Spain. |
| Subdivision Type: | Country |
| Subdivision Name: | Spain |
| Subdivision Type1: | Autonomous community |
| Subdivision Name1: | Gipuzkoa |
| Subdivision Type2: | Province |
| Area Total Km2: | 16.76 |
| Population Density Km2: | auto |
| Timezone: | CET |
| Utc Offset: | +1 |
| Timezone Dst: | CEST |
| Utc Offset Dst: | +2 |
| Website: | www.asteasu.eus |
Asteasu (in Basque pronounced as /as̺teas̺u/) is a town located in the province of Gipuzkoa, in the autonomous community of Basque Country, in the north of Spain.