Vallvik is a locality situated in Söderhamn Municipality, Gävleborg County, Sweden with 258 inhabitants in 2010.
Vallvik mill was built in 1907 and is a sulphate pulp mill belonging to Rottneros AB.
In the community there are old construction villages that were designed by Torben Grut. Vallvik, located at the so-called Virgin Coast ()(named after the large island Storjungfrun in the archipelago), has a campsite and swimming beach with beach volleyball.