Abstract: In order to fully describe the time-varying characteristic of the sea clutter and its local singularity, the multifractal theory is introduced to the analysis of radar sea clutter. The multifractal parameters of sea clutter are extracted theoretically, analyses the multifractal spectrum, quality index and singularity index of measured sea clutter data are analysed. The results show that the sea clutter has the characteristics of multifractal features and it can well explain its inherent nonlinear characteristics. Compared with the traditional statistical method, the multifractal analysis method is more accurate than the traditional method in describing the generation mechanism of sea clutter, which provides a basis for radar target detection based on multifractal theory.