Abstract: To understand the effects of hypoxia stress on growth, development and population dynamics of Plutella xylostella, and reveal relevant mechanisms underlying the hypoxic adaptation.We raised P. xylostella strain Fuzhou-S in greenhouses in Fuzhou and Lhasa, respectively. The temperature, air relative humidity and photoperiod of both greenhouses were (25±1)℃, (65±5)% RH and 8L:16D. Growth and development data in both locations with consecutive three generations were recorded. We then constructed age-stage, two-sex life tables of Fuzhou-S in Fuzhou and Lhasa.Compared with the DBM raised in Fuzhou, the results showed the hypoxic environment can shorten developmental periods of all instars (egg, larva, pupa and adult). Significant reduction of duration in the first generation was observed, while the difference decreased along with the time. Fecundity and survival rate did not change significantly. There were significant differences in the population dynamics of Fuzhou-S raised in Lhasa and Fuzhou. Intrinsic rate of increase (r), finite rate of increase (λ) and net reproductive rate (R₀) were significantly lower, but mean generation time (T) was significantly lower in the first generation and significantly increased in the second generation.P. xylostella showed its tolerance to hypoxia within first two generations, where fitness cost was found by showing significant shortening developmental duration. In the third generation, fecundity, survival rate and relative population dynamics parameters r, λ, R₀, T didn't show much difference between Fuzhou-S raised in two locations. We propose fast adaptation of P. xylostella to hypoxia may facilitate its rapid spread and colonization onto the plateau. Further analysis based on the molecular data could help untangling mechanisms underlying its adaption.