Abstract: The morphology and structure of root nodules in 8 legume species were observed. The result showed the root nodule of 8 legume species were in various shapes, and they were divided into finite nodule and infinite nodule. The shape and size of nodule were correlated with nodule types. Legume species had the same nodule structure to the legume crops, which was cortex, vascular bundle and bacteriocyte area. But some special nodule cambial cells were found in cortex, which was related to the nodule cassation and differentiation of vascular bundle to some extend. The vascular bundle of legume species were well developed and there was stele structure including ringed vessel , sieve tube and fiber cell in the nodule under investigation.