© 2020, © 2020 Informa UK Limited, trading as Taylor & Francis Group.Prey-stage preference, functional response, numerical response, and mutual interference of Typhlodromus bagdasarjani Wainstein & Arutunjan feeding on Eotetranychus frosti (McGregor) (Tetranychidae) were determined at 25 ± 1ºC, with 16:8 h L: D, at an average daily relative air humidity of 60 ± 10% on apple leaves. The results of the no-choice experiment on E. frosti revealed that the predator T. bagdasarjani consumed significantly more eggs than other prey stages. In the choice experiment, the predator showed a significant preference for E. frosti protonymphs, followed by larvae, whereas preference for consumption of eggs or deutonymphs was less. Likewise, T. bagdasarjani demonstrated a type II functional response on protonymphs of E. frosti. The attack rate (a) and handling time (Th) coefficients of a Type II response were estimated by fitting Rogers model to the data. The oviposition rate increased at the highest prey density and tended to stabilize when prey density was greater than 32 prey/day. The negative value of the interference coefficient (−0.159) in the mutual interference analysis showed an inverse relationship between the predator density and per capita searching efficiency. The results of this study revealed that T. bagdasarjani can play a role in controlling E. frosti populations, particularly when prey densities are low.