Abstract: The impact of forest landscape composition on abundance of predatory natural enemies (Chrysopidae, Vespidae) and their biological control of Lithocolletis populifoliella Trietschke is researched, which can provide theoretical basis in applicating landscape configuration methods to control forest pests. Based on remote sensing image classification maps, the impact of forest landscape composition on two predatory natural enemies and their biological control of L. populifoliella were analyzed at four spatial scales (0.25, 0.50, 0.75, 1.00 km) in utilizing principal component analysis and linear mixed effects models. The results showed that increasing the ratio of forestland to farmland in the landscape of the Karamay carbon sink forests could maintain a high abundance of natural enemies and increase their effects of biological control. Hence, proper landscape composition boosts the population of beneficial insects in the forest, and strengthens the capacity of biological control by natural enemies.