Lygus lucorum (Meyer-Dür) is a key pest of Bt cotton in China. This study reports on its flight potential examined by a flight-mill system. We found that 10-d-old mated females engaged in flight over the greatest distance (40.1 +/- 5.2 km) and duration (7.7 +/- 1.0 h) in 24-h flight assays in relation to age, sex, and mating status. Optimum temperature for flight was 20 degrees C, and optimum relative humidity was 75% RH. Flight potential of 10-d-old mated females under the optimum conditions (20 degrees C and 75% RH) was tested continuously for 48 h. Results showed that the flight distance amounted to 67.3 +/- 9.7 km, with a maximum distance of 151.3 km. This study shows that L. lucorum has the potential to undertake long-distance flight. The information will help in the development of the forecast and management of L. lucorum.