13C CP/MAS NMR experiments are carried out for polyfy-n-octadecyl L-glutamate) as a function of temperature, in order to elucidate dynamic and conformational features in the solid state and liquid-crystalline state. From these experimental results, it is found that the main chain of the polymer takes on a right-handed-helical conformation within the temperature range from 27 to 100 C, while long n-alkyl side chains take on an all-trans zigzag conformation in the crystalline stateat room temperature and are in a mobile state above 35 C. Further, it is found that at about 40 Cthe-helical main chain in the liquid-crystalline phase is undergoing molecular motion at a frequency of ca. 60 kHz.