The natural occurrence of fumonisin B-1 (FB1) and fumonisin B-2 (FB2) has been investigated in 26 maize inbred lines grown in Italy and in 72 maize hybrids grown in Croatia (19), Poland (7), Portugal (9), Romania (6), Benin (9), and Zambia (20). The incidence and levels of fumonisin contamination resulted in two major groups of countries. The first with high contamination included Italy, Portugal, Zambia, and Benin, with incidence of 100, 100, 100, and 82%, and fumonisin (FB1 + FB2) levels up to 2850, 4450, 1710, and 3310 ng/g, respectively. The second group, including Croatia, Poland, and Romania, showed very low levels of contamination (less than or equal to 70 ng/g) with 50% incidence of positive samples. A general trend for higher contamination levels was observed in maize genotypes with higher FAO maturity class or dent-type endosperm. Although the environmental conditions of the specific area of cultivation seem to play a role in the formation of fumonisin in maize, further investigations are needed to thoroughly establish the genotype-area-season interaction.