AbstractI have observed sea clutter including a target (small ship) using an S‐band radar with a frequency of 3.05 GHz, a beamwidth of 1.8°, a pulsewidth of 0.5 μs, and a pulse‐repetition frequency of 1600 Hz. To investigate the sea clutter amplitude statistics, I introduce the Akaike Information Criterion (AIC). I have found that the sea clutter amplitudes obey the log‐normal distribution with the shape parameter of σ = 0.385 for entire data and the log‐normal,Weibull, and log‐Weibull distributions with the shape parameters of σ = 0.379‐0.505, c = 2.92‐4.81, and c = 12.33‐15.28, respectively, for data within the beam width of an antenna. The number of the smallest AIC (MAIC) of the log‐normal, Weibull, and log‐Weibull distributions to data are 3, 5, and 4, respectively, from 12 range sweep numbers. I have used the Weibull/CFAR (constant false alarm rate) circuit which is modified a Cell‐Averaging (CA) LOG/CFAR circuit. It is found that small ship is detected and sea clutter is suppressed with improvement of 24.83 dB by Weibull/CFAR.