The integrated guidance and control (IGC) is a method to improve the traditional separation guidance and control design for unmanned aerial vehicles (UAV). The advantage is that this design fully considers the coupling relationship between guidance and control loops, and the full-state control of the UAV can be taken into account, thereby improving the accuracy of guidance. This paper provides a review and discussion of current work on the design of IGC systems. The difficulty in designing an IGC system is that the order of the IGC system is high, and the coupling between states is strong, making the controller design difficult. Its research focuses on IGC methods that satisfy complex multi-constraint conditions, IGC methods with rapid convergence and strong robust IGC methods under uncertainty and unknown disturbances, etc. This paper also discusses possible future work on IGC methods of UAVs, including fault-tolerant and anti-noise IGC methods under harsh working conditions, cooperative IGC design of UAVs and intelligent IGC methods.