This study was devoted to investigating the flight characteristics of joined-wing aircrafts by means of design, manufacture, and flight test of actual vehicles, in order to evaluate the feasibility for application to unmanned aerial vehicles. There were two developing stages. The design of joined-wing UAV of the first stage was based on the results and suggestions of literatures. Manual and automatic flight tests of this UAV were both successful. The stability and controllability were suitable except when the Reynolds number was less than 1.8×105. The design of the second stage was improved according to the test results of stage one. The stability and control quality were proved to be better. The joined-wing configuration is adequate for autonomous unmanned aerial vehicles.