Abstract: The presence of ionospheric clutter in high-frequency surface wave radar(HFSWR) may extremely affect the performance of radar system and degrade the capability of detecting target. In order to obtain clutter parameters accurately and suppress ionospheric clutter better, a single snapshot parameter estimation method based on compressive sensing(CS) is proposed for estimating the spatial domain and polarization domain parameters of ionospheric clutter. Based on the block sparse estimation model of polarization sensitive array, this method uses block orthogonal matching pursuit(BOMP) algorithm to realize joint estimation of angle and polarization parameters of single snapshot in range-Doppler domain, and further obtains the spatial angular spectrum and polarization spectrum of target and clutter. For arbitrary polarization-sensitive arrays, the performance of estimation is better than that of traditional methods under the condition of single snapshot in range-Doppler domain, and the computational complexity is very low, so real-time processing can be realized. The simulation results and the data processing results of a HFSWR system show that the parameter estimation method is effective.