Temperature is known to play a crucial role in the population dynamics of insects. Insects have evolved different mechanisms to resist unfavorable temperatures. In recent years, western flower thrips (WFTs), Frankliniella occidentalis (Pergande) have caused serious damage to vegetable crops, so that, a study about the effects of heat stress on the thrips species is warranted. We exposed various developmental stages of WFTs to 41°C, 43°C, or 45°C for 2 h to determine the effects of heat stress on survival rates, the parental reproduction, and its offspring, the activity of acetylcholinesterase and the trehalose level. Prepupae and pupae have the highest level against heat resistance than larvae and adults with higher survival rates after exposure at 41 or 43°C for 2h, but that of adults was higher at 45°C. The survival rates of larvae were lowest. Longevity of female adults and the quantity of larvae and adults in the first generation decreased significantly after exposure to high temperature. Activities of acetylcholinesterase were significant higher after heat stress treated, but the activity of acetylcholinesterase of pupa was significant lower after been exposed to 45°C for 2h. The trehalose levels in different developmental stages were significant lower after heat stress treatment. The activity of acetylcholinesterase and the trehalose level in the first progeny generation changed obviously after exposure the parental individual. These results support the hypothesis that heat stress may be used to control WFTs.