Laboratory studies were conducted to determine host-mediated effects of plant cultivars onPediobius foveolatusCrawford. ‘Henderson Bush’ lima bean and ‘Bonus’, ‘Williams’, and ‘Cutler 71’ soybean were studied. Immature survival and longevity, and adult longevity and fecundity data were used to construct life tables forP. foveolatusparasitizing Mexican bean beetle (MBB),Epilachna varivestisMulsant, larvae on each cullivar. Fewer viable mummies and parasitoid progeny per host were produced on ‘Cutler 71’, but cultivar did not significantly affect fecundity. Consequently, relative to ‘Cutler 71’, the intrinsic rates of increase ofP. foveolatuson the other cultivars were ca. 1.3-fold higher. Relative to intrinsic rates of increase of the MBB on the same cultivars, these results indicated that population growth potentials ofP. foveolatuswere less affected. Additionally, MBB mortality caused by unsuccessful parasitoid ovipositions was higher on the more resistant cultivars. Therefore, the higher the resistance exhibited by a cultivar to MBB, the greater the relative impact of the parasitoid population, assuming that cultivars do not affect parasitoid searching.