High speed helicopter with coaxial rigid rotor is one of the most promising configurations for the next generation helicopter. Wind tunnel experiment is an important way in helicopter aerodynamics research and in the development of a new helicopter. The current status of wind tunnel tests on coaxial rigid rotor is examined in this paper. A brief history of the developed test facilities is given. The review is followed by the research results on different aerodynamic problems，e.g.， lift offset， flow field visualization and measurement， drag reduction of hub， propeller and fuselage test. Considering the characteristics of previous studies， the prospects of wind tunnel experiment for coaxial rigid rotor on test rig development， research capability improvement， and test results application are presented.