Technical Abstract: A 7-year field study evaluated 61 sunflower accessions and 31 interspecific crosses for resistance to attack by naturally occurring populations of three stem-infesting pests, the sunflower stem weevil, Cylindrocopturus adspersus (LeConte) (Coleoptera: Curculionidae), a longhorned beetle, Dectes texanus LeConte (Coleoptera: Cerambycidae), and a root boring moth, Pelochrista womonana (Kearfott) (Lepidoptera: Tortricidae) at two locations in the central Plains. Impact of these germplasm lines on weevil larval parasitoids also was studied. Germplasm with potential sources of resistance to attack from all three stem-infesting species were revealed. Accessions PI 650558, PI 386230, PI 431516 were consistent in averaging low densities of stem weevil larvae per stalk among lines tested and PI 497939 exceeded 25 weevil larvae per stalk in only one year of five years of trials. A number of interspecific crosses also had consistently low densities of C. adspersus larvae per stalk. Populations of both D. texanus and P. womonana were variable over years, but differences among the lines tested were evident in many trials, revealing potential for developing resistant germplasm. Four accessions (PI 386230, PI 431542, PI 650497, and PI 650558) had low larval densities of C. adspersus and P. womonana in addition to reduced percentage infestation by D. texanus. Seven species of hymenopteran parasitoids were identified from C. adspersus larvae during the study, but rates of parasitization were generally low (mean ranged 0.1 to 3.1% among years) and in most cases significant differences were not evident among the lines tested. Results showed potential for developing resistant genotypes for these pests. The prospect of adding host-plant resistance as an integrated pest management tactic would provide another tool for reducing economic losses from stem-infesting insect pests of sunflower in the central Plains.