This study shows the effectiveness of deliberately selecting for Coptera haywardi individuals to increase a population’s capacity to discriminate against parasitised hosts. In the ‘selected colony’ (F1–F4), females were selected based on their ability to discriminate parasitised fruit fly pupae, determined by their host searching, foraging and oviposition behaviour. Female parasitoids of successive generations of the selected colony (F1–F4) showed an increasing discriminatory ability, including reduced host searching and foraging time. The last selected generation, i.e. F4 showed an increase in fecundity compared to the standard colony. In F4 individuals from the selected colony, antennae length increased but the hind tibia size did not, compared to individuals from the control colony. Flight ability and survival remained unchanged across all generations. This selection process could be an effective method of recuperating the discriminatory capacity of a C. haywardi colony under mass rearing conditions.