Insecticides are one of the most effective ways to control pests. However, with the long-term and widespread use of insecticides, insects have acquired reduced sensitivity to them, resulting in resistance. How to overcome the resistance of insects becomes an important issue in integrated pest management. Recently, with the development of genome sequencing and genetic manipulation techniques, the research on insect resistance has led to many important breakthroughs, providing a theoretical foundation for the control of pests. In this paper, we present the history and mechanism of common insecticides, paying special attention to the mechanisms of insecticide resistance from three aspects:target resistance, metabolic resistance, and penetration resistance. Point mutations at the insecticide site of action reduce the affinity of the target to the insecticide. Activation of the cytochrome P450 enzyme and the glutathione transferase systems increases the degradation of insecticides. Changes in the structural components of the epidermis and an increase in the ABC transporter can effectively block the penetration of the insecticide in the insect. The use of genetic manipulation or inhibitors to regulate the key steps of the above three resistance mechanisms may become a new strategy for future pest control.