Petersfield is a market town and civil parish in the East Hampshire district of Hampshire, England. It is north of Portsmouth, via the A3 road. The town has its own railway station on the Portsmouth Direct Line, the mainline rail link connecting Portsmouth and London. Situated on the northern slopes of the South Downs, Petersfield lies wholly within the South Downs National Park.
The town is on the crossroads of well-used north–south (formerly the A3 road which now bypasses the town) and east–west routes (today the A272 road) and it grew as a coach stop on the Portsmouth to London route. Petersfield is twinned with Barentin in France, and Warendorf in Germany.