Our study aims to see the influence of temperature and phenological stages of strawberry plants on the development of the pest mite Tetranychus urticae and the predatory mite Phytoseiulus persimilis. It appears from this study that the yellow mite marked its presence from the early stages of crop development in the form of winter females. The density of this species has evolved as the temperature increases, reaching a maximum plateau in March which coincides with the fruiting stage (T4) where temperatures vary between 21C and 27C. The first appearance of Phytoseiulus persimilis is marked during this month. This predator reached its maximum in April when the average temperature is 31C. the yellow mite population fell and the infestation rate was less than 5% in May, which corresponds to the stage of senescence and onset of rest (T5) where temperatures vary between 33C and 40 C. The density of the predator then decreased in parallel and was zero during this stage