The detection of small floating targets in strong sea clutter is a hot topic and difficult problem in maritime radar detection.Traditional algorithms have poor detection performance in a single domain (time domain, Doppler domain and time-frequency domain).Feature-based detection algorithm is an effective means to detect small floating targets on the sea surface.A feature fusion detection algorithm based on full polarization is proposed.Six features in time domain and Doppler domain are selected, six features based on full polarization are extracted, and the separability of features is analyzed.Finally, PCA-based anomaly detector is used for fast target detection, and is verified on the measured IPIX radar data set.The experimental results show that compared with the existing PCA-based algorithm, the proposed algorithm has better detection performance.