A method of estimating ocean wave directional spectra using a>high-frequency (HF) radar with a single antenna array was applied to actual ocean data. This method incorporates the wave energy balance equation and the continuity equation of wind vectors into the inversion method to solve the integral equation which relates a Doppler spectrum to wave spectra. This method uses dynamic extrapolation to estimate wave spectra at positions where the signal-to-noise (SN) ratio in Doppler spectra is not high. The agreement of wave heights with in situ observation is good. Additionally, there is a correlation between radar-estimated sea surface winds and winds near the HF radar observation area. The method under consideration was found to be able to estimate wave directional spectra in swell conditions.