In the application of remote sensing, X-band radar based on the land is an appropriate technique to monitor sea states and to provide time-dependent wave field. Fourier transform (FT) is the common algorithm to capture the wave information from radar images, under the assumption of homogeneous wave field. However, the nearshore wave field is non-homogeneous for the local refraction, shoaling and other nonlinear mechanisms, leading to ambiguity of wave characteristics if calculated by FT. The two-dimensional wavelet transform (2-D WT), which is skillful in catching local information, is introduced here to analyze radar images. The spatial spectrums of six different space locations are used here to compare the performance of FT and 2-D WT. The conclusion indicates that the 2-D WT implemented here is better than the FT for capturing non-homogeneous characteristics of nearshore wave filed from radar images.