Cotton is an industrial plant with a high commercial value. It is used in various fields such as textile, food (cotton oil), gunpowder industry, paper, and furniture production. One of the most important problems encountered during cotton production is insects that feed on cotton and cause economic loss. The intensive amount of pesticides is used by the producers for the control of pest insects. As insects gain resistance to pesticides over time, the amount of chemical pesticides applied is gradually increasing. Chemical products are quite harmful to both living things and the environment. For this reason, there is a need to popularize biological control methods instead of using pesticides to control pests. In this chapter, detailed information about insect species causing damage to cotton and biological control methods is given.