We measured survival, developmental time, and fecundity of the omnivorous predatory mite Amblyseius cucumeris on diets of pollen, western flower thrips (WFT), or a combination of the two. Different diets significantly affected A. cucumeris survival and the duration of development. When supplied only with water, almost all A. cucumeris died as protonymphs, and the few that developed to deutonymphs did not survive beyond that. Pollen alone allowed development to the adult stage but the mortality was very high; only 6% became adults and these died before reproducing. Immature survival was much higher and development time shorter when A cucumeris was supplied with either WFT or WFT plus pollen, but there were no difference between these two treatments. There was no difference between in number of eggs laid per adult female when either WFT or WFT plus pollen were available. However, longevity of adult females and the duration of their oviposition was longer when supplied with WFT plus pollen. When WFT plus pollen was available, immature A. cucumeris consumed fewer WFT than when WFT were available without pollen, but the difference in adult WFT consumption between the two treatments was not significant.