Macrosiphum euphorbiae (aphid) is an important economic pest because it causes significant damage to several crops, notably on strawberry. The use of natural enemies, especially predators, is an alternative that is being explored to protect strawberry crops against this pest, notably the species Orius laevigatus is a promising predator for biological control. However, the lack of suitable habitats and/or food is a constraint to the growth and/or the establishment of the predator populations, reducing their effectiveness as control agent against M. euphorbiae. Using additional food resources such as companion plants or alternative food sources may support predator population and associated biocontrol services they provide. The objective of this study was to evaluate the efficacy of O. laevigatus as biological control agent against M. euphorbiae, mediated by the presence of companion plants and alternative prey. We evaluated under greenhouse conditions the effect of Lobularia maritima (alyssum) as possible companion plant, as well as Ephestia kuehniella eggs as alternative prey, on O. laevigatus populations and biocontrol service in strawberry cropping system. Predators were placed in the presence or absence of alyssum and/or E. kuehniella eggs on strawberry plants previously infested with aphids. We showed that the presence of alyssum and/or E. kuehniella eggs enhanced O. laevigatus population growth (when compared to a control group). Furthermore, we observed a steady reduction of M. euphorbiae populations when the companion plant was present alone or when it was associated with the alternative prey. Finally, the treatment with the combination of alyssum and alternative prey resulted in the highest yield (number of fruits per plant). Our study demonstrated that combining alyssum, as a companion plant, and E. kuehniella eggs, as an alternative prey, could be an effective option for establishing O. laevigatus populations and for controlling aphids in strawberry cropping systems.