Abstract: The flight activity of lesser grain borer,Rhyzopertha dominica(Fabricius),were tested by a computer monitored flight mill system and flight chambers in seven different temperatures.The results showed that R.dominica could flight above 20℃,and the optimum temperature for flight initiation was 32℃.The average speed of flight for females and males increased initially and then decreased with the increase of the measured temperatures,the top average speed appeared at 35℃ and 32℃ respectively.The total flight distances and flight durations in 24 h of female adults were the lowest at 20℃,but there was no significant difference between 23℃ and above tested temperatures.The total flight distances and total flight durations in 24 h of male adults both increased initially,then decreased with the increase of the measured temperatures,they reached the maximum at 32℃.Flight activity of lesser grain borers presented a certain rhythm,which showed frequency flight was higher than the daily average level at 13:00-21:00,while they became the highest at 15:00-16:00.The results enrich the flight behavior information of R.dominica and can provide reference for the prevention and light trap technology of lesser grain borer.