The protective agent A, the mixture C and the mixture D were screened from five kinds of protective agent, and they have good touch-killing effect on tobacco beetles. Six kinds of insect-proof plastic bags were made that were marked A1, A2, C1, C2, D1, D2 respectively. The experiment was carried out in Longyan and Xiamen cigarette factory where the insect-proof plastic bag (inside lining) was used to prevent tobacco beetles from second invasion. The results showed that six kinds of insect proof plastic bags (inside lining) had good effect on preventing beetles and the duration of insect-proofing reached 32 months. The loss rate caused by beetles was 3.54%, 1.49% and 1.03% respectively in Xiamen cigarette factory and the loss rate was 2.14% and 1.25% respectively in Longyan cigarette factory by use of ordinary plastic bag (inside lining), but the strips eaten by beetles were not found when using insect-proof plastic bag. The insect-proof plastic bag had no bad influence on the qualities of the strips.