The diet of the California quail (Callipepla californica) was determined following analysis of the contents of the crop and muscular stomach of 124 individuals captured in Nuble province, VIII Region of Chile during the summer of 1995 (N = 96) and the winter of 1999-2001 (N = 28). In summer, 35 different types of seeds were observed, of which Vicia spp., Lolium spp., Tritricum spp., Cyperus spp., Echium vulgare and Silena gallica were the predominant seeds and represented more than 50% of the total weight of the diet. Arthropods represented 0.16% of the stomach contents, of which the most important was Dichropus araucanus (araucan lobster). In winter, 25 different seed species were observed, of them Convolvulus arvensis and Acacia spp. were up to 44% of the total weight of the diet. Weed seeds represent the largest component of the California quail diet, followed by agricultural seeds and then native seeds. The differences in seasonal diet are discussed with comparisons to data for the same species from other regions.