The influence of various life diets on the biology and demographic parameters of the predatory mite, Agistemus olivi Romeih, was studied under laboratory conditions. A. olivi successfully developed and reproduced on all of the tested eriophyid mites. Feeding on Aceria mangiferae Sayed enhanced the development of A. olivi, resulted in the shortest mean generation time and was the most commensurate food for the ovipostion of the predator, as exhibited by the highest fecundity and net reproductive rate. Preying on Aculops lycopersici (Massee) gave the lowest fecundity and net reproductive rate; therefore, this prey was the least suitable for the oviposition of A. olivi. Preying on Aculus fockeui (Nalepa et Trouessart) and A. mangiferae produced higher intrinsic rates of increase and finite rates of increase for the predator in comparison to A. lycopersici, which showed the lowest value. These differences in response to various eriophyid pests should be considered for the production of healthy cultures of A. olivi.