Susceptibility to the maize weevil,Sitophilus zeamaisMotschulsky, of corn lines bred for their resistance to the aflatoxin-producing fungusAspergillus flavusLink ex Frics was determined in the laboratory. Duration of maize weevil development, number of progeny produced, and an index of susceptibility varied with corn line; number of eggs laid and survivorship from egg to adult emergence did not vary with corn line. Soluble carbohydrate, kernel hardness, lipid, soluble nitrogen, free and bound phenolic acids, Kjeldahl protein, and protein/carbohydrate ratio varied with corn line; equilibrium moisture content did not vary with corn line. The only relationship between biological parameters of maize weevils and chemical lild physical properties of the stored corn that was predictable was that maize weevil development time increased as lipid content of the corn increased. Susceptibility toA. flavusinfection in the field was not correlated with susceptibility to maize weevil population growth or with chemical or physical properties of the stored corn. Predicted weevil population growth over a 180-d period varied 50-fold among the corn lines. Some of the corn lines that are less susceptible to infection byA. flavusin the field were also less susceptible to maize weevils (particularly Mp420 and SC54).