The morphology of high cis-1，4-polybutadiene crystallized at low temperature and the change of morphology at room temperature with the content and structure of sol and gel．and with different degree of extension and different time of relaxa-tion were studied with electron．and optical microscope．It is shown that the supermolecular strutture of the amorphous cis-1．4-polybuta-diene rubber at room temperature is not homogeneous

but consists of domains with certain regularity．Its fundamental structure units are nodulc，aggregation of no-dules and cluster of gel．The structure units and the junction between them are dependent upon the molecular weight and the gel content of the samples；and in turn the extension and relaxation behaviour of the rubber samples depend on their supermolecular structure．