The aim of this paper is to complete the knowledge of the Macrolepidoptera fauna present in the province of Alessandria, with the addition of further findings of species not included in previous contributions (Cabella & Fiori, 2006, 2010). Each species is accompanied by brief notes on its Italian distribution and phenology. After the systematic list, an area of particular faunistic interest, the Apennine zone of Guardamonte in the municipality of Gremiasco/San Sebastiano Curone in Val Curone, is highlighted. [ABSTRACT FROM AUTHOR]