Abstract: This paper studies mainly the fractal property of the real sea clutter in frequency domain and the effects of different parameters to the fractal characteristics of the sea clutter spectrum. Firstly, this paper takes Fractional Brownian Motion (FBM) for example and interprets detailedly that the spectrum of the FBM is fractal on condition that the FBM time series is fractal. Then, X-band and S-band real sea clutter are used for the verification of the fractal property of the real sea clutter spectrum. At the same time, the effects of the different parameters are analyzed. The results show that the spectrum of the real sea clutter is self-similar in statistical meaning, namely it is fractal. Additionally, it is found that the fractal characteristics of the sea clutter and target echoes in frequency domain are different to some extent and this difference has the potential for weak target detection within sea clutter.