Predatory phytoseiid mites as biocontrol agents are increasingly used in pest control programs across the globe, and Neoseiulus cucumeris (Oudemans) is one of them, which is a commercially available agent against various pests of greenhouse crops. This generalist predatory mite can feed on different foods and diets, including small arthropods and pollen. Feeding and reproducing on a pollen diet is a considerable characteristic of this predatory mite that facilitates the cost-effective production of large numbers of this predator so-called mass rearing. Therefore, the effects of saffron (Crocus sativus L.) pollen as an alternative food source on development and reproduction of N. cucumeris were determined over 20 successive generations. In addition, the predation ability of the nymphs and adults of N. cucumeris being switched to natural prey, Tetranychus urticae Koch after 10^th and 20^th generations was evaluated. The shortest and longest developmental time happened in the 1^th and 5^st generations, respectively. The predator in the 1^st and 20^th generations had a higher intrinsic rate of increase (r) (0.171 and 0.170 day^-1, respectively) than other generations, while the 5^th generation had the lowest value of this parameter. The development and fecundity of N. cucumeris was not significantly different when this predator switched to a diet of T. urticae. The results of this study revealed that rearing of N. cucumeris for 20 generations on saffron pollen did not affect the performance of the predator negatively and this alternative food source can be used for the mass rearing of N. cucumeris.