Sunflower species (Helianthus) were evaluated for resistance to a stem weevil,Cylindrocopturus adspersus(LeConte). In greenhouse tests, foliar feeding byC. adspersusadults was significantly less in 11 of 18 annual and in 13 of 34 perennial species tested than in commercial hybrid ‘894’. The number ofC. adspersuslarvae recovered was significantly lower in eight annual and all perennial species than in hybrid 894. Significantly fewer larvae ofC. adspersusoccurred in 27 perennial species ofHelianthusin the field during 3 consecutive years (1981–1983) than occurred in nearby wildH. annuusL. or hybrid 894. However, the number ofC. adspersuslarvae found in F1progeny of interspecific crosses between the wild species and cultivated hybrid parental lines in the field was equivalent to the number of larvae found in the cultivated parents.