Abstract: Altimeter waveform at sea can be classified as two basic waveform types,one specular waveform and the other diffuse waveform.A waveform moving correlation analysis method(WMCA) is presented to altimeter waveform classification over non-open oceans.The experiments with ERS-1/GM waveform over coastal waters and Antarctic oceans show that pulse peakiness,β-5 and WMCA can do waveform classification and have similar results.