We evaluated annual glandular-haired diploids, Medicago disciformis DC. and M. blancheana Boiss., and tetraploids, M. rugosa Desr. and M. scutellata (L.) Mill., for resistance to adult alfalfa weevils, Hypera postica (Gyllenhal), in a growth chamber. Perennial M. sativa L. control cultivars were: ‘Arc’ (tolerant to alfalfa weevil larvae), ‘Lahontan’ (susceptible), and ‘San Pedro’ (weevil resistance unknown but with simple hairs on stem and leaves). The glandular-haired annual species were more resistant to feeding than the M. sativa cultivars in free-choice tests with attached leaves, excised leaves, and attached stem terminals. Since resistance was the same for attached and excised leaves, excised leaves may be used to evaluate resistance. Diploids were more resistant than tetraploid annual species in the leaf tests. Measured by the number of weevils visiting plants in the stem-terminal, freechoice tests, M. sativa cultivars were more attractive than the annual species. The ranking was similar in the no-choice, excised-leaf test, except for the simple-haired San Pedro ranking between the diploid and tetraploid annuals.