In the greenhouse, seedlings of 235 plant introductions of Lycopersicon were screened for resistance to the tomato pinworm, Keiferia lycopersicella (Walsingham). In initial screenings, accessions of Lycopersicon Pimpinellifolium (Jusl.) Mill. and L. esculentum × L. Pimpinellifolium were more susceptible while those of L. peruvianum (L.) Mill., L. peruvianum var. humifusum. Mull., L. esculentum × L. peruvianum, L. cheesmanii f. minor (Hook F.) Mull., and L. glandulosum Mull. were less susceptible than the commercial tomato cultivar ‘Walter’ (L. esculentum Mill.). Selections of L. hirsutum Humb. and Bonpl. and L. hirsutum f. glabratum Mull, were most resistant and had 25–50% less damage and 50–75% fewer larvae than Walter. In secondary screening, accessions of L. cheesmanii f. minor, L. glandulosum, L. hirsutum and L. hirsutum f. glabratum had less damage and fewer larvae per plant than Walter. In a laboratory study with excised leaflets, larval survival and weight were less on P. I. 126445 and P. I. 127826 (L. hirsutum) and P. I. 126449 (L. hirsutum f. glabratum) than on Walter.