Abstract: Objectives The target information error of forced reconnaissance is large, and the course is variable. This leads to a decrease in target maneuver detection performance. Furthermore, it affects the analysis of the target intention. Therefore, this paper proposes a maneuvering target detection method based on the prior knowledge. Methods It introduces two prior knowledge through solidifying expert experience. Based on the definition of trajectory smoothness measurement, a calculation method for course maneuver evaluation factor based on principal component analysis is proposed. Then, target detection is achieved based on course maneuvering factor and maximum filtering. Results The simulation results indicate that compared with mainstream interacting multiple model, the proposed method provides more accurate detection results for target maneuvering detection but with least missed detections.Conclusions The results of this study prove progressiveness of the proposed algorithm.