Abstract  [Aim]  To investigate the impact of Orius sauteri on the population dynamics of peanut aphids in a peanut-maize strip intercropping system. [Methods]  A comprehensive field experiment (peanut-maize strip intercropping system and peanut monoculture system) was conducted in 2017 to investigate the population dynamics of peanut aphids and their primary predator, O. sauteri. This involved calculating the ratio of beneficial natural enemies to pest insects in both monoculture and intercropped systems, and conducting a molecular gut-content analysis to assess the predation of peanut aphids by O. sauteri under realistic field conditions. [Results]  The population peak of O. sauteri occurred earlier than that of peanut aphids in peanut-maize intercropped fields. During the colonization period of the peanut aphid (before June 10th), peanut-maize intercropping significantly increased the density of O. sauteri compared to monoculture systems. Throughout all sampling dates (from May 31th to July 20th), comparative analysis revealed that peanut-maize strip intercropped fields had a significantly higher predator-to-pest ratio compared to peanut monocultures (t=2.981, df=10, P=0.014). During the population peak of peanut aphids (on June 10th), peanut-maize strip intercropped fields had a significantly higher predator-to-pest ratio compared to peanut monoculture fields (t = 7.103, df = 4, P = 0.002). On June 10th, 9.21% of predators tested positive for peanut aphid DNA, with nonpositive results obtained during other periods. [Conclusion]  Our findings demonstrate that intercropping strips of peanuts and maize substantially increases the predator-to-pest ratio compared to growing peanuts as a monoculture. Furthermore, early predation by O. sauteri on peanut aphids significantly reduces the population density of peanut aphids during the peanut seedling stage.