The gall mite, Aceria pallida Keifer (Acari: Eriophyoidae) is an economically important pest of wolfberry Lycium barbarum L. and can cause significant losses to plant production. Two species of phytoseiid predatory mites, Amblyseius andersoni Chant and Neoseiulus neoreticuloides Liang & Hu were found on L. barbarum in Bayan Nur city, Inner Mongolia, China. We assessed the potential of these two phytoseiid species as biological control agents against A. pallida, using functional response experiments with seven prey densities (5, 10, 20, 40, 60, 80 and 100 adults of A. pallida) on a wolfberry leaf under 25ºC ± 1ºC, 60% ± 5% RH and a 16:8 h (L:D) photoperiod. Overall, the predation of both species increased with increase in prey density. The consumption of A. andersoni female was significantly greater than that of conspecific males and N. neoreticuloides female at high prey densities. Both phytoseiid species displayed a type II functional response to A. pallida. Female A. andersoni had a higher attack rate (5.961) and a shorter handling time (0.014 d) than male A. andersoni (1.619; 0.019 d) and female N. neoreticuloides (0.719; 0.023 d). The maximum attack rate (T/Th) was estimated to be 71.43 and 52.63 for female and male A. andersoni, respectively, while it was 43.48 for female N. neoreticuloides. Both female and male A. andersoni consistently consumed significantly more prey than N. neoreticuloides across all densities of A. pallida adults.