A greenhouse study was conducted to investigate the host-pest relationships of seven cultivars of strawberry, Fragaria spp., that differed in resistance to the twospotted spider mite, Tetranychus urticae Koch. Plants were infested with a homogeneous density, of females per unit of leaf area. Mite population development and plant damage were monitored on a weekly basis for 6 wk on initially infested and subsequently colonized leaves. Cultivars differed in their support of mite populations and in sensitivity to mite damage from the second to the fifth week of the experiment. 'Floridabelle' showed antibiotic and antixenotic characteristics by supporting the lowest population density and showing lower damage values than other cultivars. 'Totem' demonstrated high levels of tolerance by withstanding higher populations than other cultivars with damage comparable to that of resistant clones. 'Canoga' and 'Profumata di Tortona' showed hypersensitive responses to relatively low populations. 'Rainier', which supported high populations and demonstrated high overall damage values, was susceptible. 'Chandler' and 'Selva' demonstrated resistance patterns which were intermediate. Resistance to the twospotted spider mite appears to be qualitative because it is conditioned by different mechanisms among cultivars