Polarimetric ground-based synthetic aperture radar (GB-SAR) measurements in a paddy field and its analysis results are presented. The measurements were carried out three times before and after an ear emergence of rice, and SAR images of full polarimetric components are reconstructed from the acquired dataset. By using those images, a sensitivity of a polatimetric component and a frequency range due to the ear emergence is discussed. Then, we could confirm that HH component of C-band is the most sensitive parameter although HV and VV components do not give significant changes. Especially, HH component of 5-6GHz and 6-7GHz show 10dB increases after the ear emergence. Moreover, Freemen decomposition is applied to the SAR images. And, increases of a surface scattering component and a double bounce component in a same frequency range with the increase of HH component can be observed.