Abstract: The paper aims to identify the species and regularity of thrips happened on leek, and to study the main control methods. The authors identified thrips species by morphological and molecular methods, and studied the damage symptoms, biological characteristics, occurrence regularity and control methods of thrips in the field of leek. The results showed that: the morphological characteristic of thrips on leek was Frankliniella occidentalis (Pergande), the results of ITS molecular identification showed that the amplified fragment 520 bp was similar to that of the F. occidentalis, and the similarity of the base sequence was 99.81%; the space distribution of F. occidentalis in the field from the height of 80 cm was relatively concentrated; on sunny days, the thrips appeared more frequently during 15:00-17:00; the lethal effect of rain on thrips was significant, the death rate was 29.30%; the results of field efficacy trials indicated that dinotefuran 20% soluble granules and 40% dacetamiprid granule had good control effects on leek thrips, and the control effect of 1500×diluted solution of 20% dinotefuran soluble granule was the best, up to 92.56%.