The high-aspect-ratio composite wing is generally used in long-endurance Unmanned Aerial Vehicle (UAV), which uses lightweight and high-specific-strength composite structure. This type of wing has significant geometric nonlinearity and aerodynamic nonlinearity during the flight, which further leads to the aeroelastic nonlinearity of the wing. There is a huge difference for design analysis method between the high-aspect-ratio composite wing and the conventional wing. In order to summarize the research status and forecast the future research direction of the high-aspect-ratio composite wing, this paper analyzes and summarizes the design, analysis and experiment methods of the existing high-aspect-ratio composite wing. The aeroelastic characteristics of wing would be affected by the geometric and aerodynamic nonlinearities. The structural design and structural analysis methods of high-aspect-ratio composite wing are introduced. Two kinds of aerodynamic analysis methods are introduced: the aerodynamic analysis method based on the strip theory and binary unsteady aerodynamic method and three dimensional aerodynamic analysis method considering spanwise flow effect. Static aeroelasticity method, dynamic aeroelastic analysis method and active control technology applied in the high-aspect-ratio wing are introduced. The recent advance in aeroelastic tailoring of high-aspect-ratio composite wing is analyzed. Finally, the experimental research progress of high-aspect-ratio composite wing is introduced. Based on the literature analysis, it can be seen that the structural model of the existing high-aspect-ratio composite wing adopts the equivalent beam plate model, while the aerodynamic model adopts the combination of the strip theory and the binary unsteady aerodynamics considering the dynamic stall. The flight test, as well as the research based on the coupling of aerodynamic reduced-order model and the structural model of the high-aspect-ratio composite wing may be the research and development directions of the high-aspect-ratio composite wing in the future.