Foraging behavior is of vital importance for predators. The resources acquired through foraging are essential for the growth, development and maintenance of the individual. Therefore, efficient searching mechanisms are indispensable for an individual’s chances of survival and reproduction. Predator foraging efficiency as well as predator foraging behavior may be influenced by both intrinsic and environmental factors. Perhaps the most interesting and influential of the environmental factors is the host plant on which herbivorous prey are encountered. Recent ecological studies have suggested that host plants play key role in tri-trophic interactions. In this work I evaluated the effects of cucumber plant architectural complexity and prey distribution on the foraging efficiency and behavior of Phytoseiulus persimilis Athias-Henriot. Plant architectural complexity represented differences in leaf number and size; however, all plants had the same total surface area. Plants with 6 small leaves were considered as complex architecture, whereas plants with only 2 large leaves were considered as simple architecture. The prey distributions were: prey patch on a single base leaf and prey patch on all leaves of each plant architecture. The foraging efficiency was assessed by measuring prey-finding time and prey-consumption rate, whereas the behavior was assessed by conducting observational studies on specific foraging activities. Phytoseiulus persimilis was able to encounter prey more rapidly on complex plants with prey patches distributed evenly within their canopy. The predatory mite spent more time foraging on the stems and petioles of the simple plants and more time on the leaves of the complex plants.