Abstract: In this paper, a simulation system of data processing algorithm for high-frequency skywave over-the-horizon radar is described. According to the special characteristics of over-the-horizon radar, some particular models are introduced to simulate the impacts of the ionosphere on the echoes, and these models are embedded in the data set used as the input of data processing terminal. The system has been implemented in the Matlab environment, emboding compatibility and entensibility. This integrated platform would be helpful for the development and design of novel data processing algorithms in the skywave syetem.