A. Bongioanni notes that Gualco is a surname of Piedmont and Liguria, derived from a given name whose more recent form, Walch, is a variant of the Germanic wala.

E. Rossoni specifies that the surname is concentrated in the Alessandria and Genoa areas, with a documented presence in localities such as Parodi Ligure, Gavi, Novi Ligure, Alessandria, Capriata d'Orba, Silvano d'Orba, Tortona and Arquata Scrivia —in the Alessandria area—, as well as in Genoa and Chiavari. According to Rossoni, the surname would derive from the medieval name Gualcus, an Italianization of a name of Germanic and also Gothic origin, Walco.