In order to study complexity and intelligent generation mechanism of UAV cluster, the concepts and methods of intelligent emergence and intelligent evolution of UAV cluster are expounded. This paper discusses the requirements and principles of intelligent emergence modeling for four application areas of UAV cluster intelligent emergence：information fusion, online task planning, search and attack optimization in unfamiliar environment and cluster formation control. This paper puts forward three evolution directions of UAV cluster intelligence, rule evolution, algorithm evolution and case evolution, and discusses the modeling approach to achieve the evolution. It can provide reference for further research on intelligent emergence and intelligent evolution of UAV cluster.