Air-coupled ultrasonic non-destructive testing technology, possessing the characters of complete non-contact and non-destruction, can be used in some situations in which traditional testing is hardly applicable. This article summarized the development of air-coupled ultrasonic non-destructive testing technology briefly, the main existing problems that restrict its progress are analyzed respectively from three processes, concluded and summarized the development and progress of the current solutions to these problems. People can promote the development of this technology more efficiently and directly by the research of its present development.