Some species of the Syrian Flora were waned, other were extincted. therefore, it was so nessesary to make a releve for restrict and classify the survival species in order to put them under conserving & improvement genetic program. The aim of this research was to study the plant diversity in West Homs; one of important basaltic region in Syria, and to concentrate on the wild legumes and the Rhizobium strains which cohabit with. A plant survey was carried out showed the existence of 365 species belong to 202 genera and 51 families, 15 species are endemic.12 species not observed previously in Syria but are found in Lebanon were recorded,in addition another 3 species not listed at all neither in Syria nor in Lebanon were mentioned. The geobotanical attributes and the economical importance of the gathered species were determined.as so as systematic keys of the most important families were suggested...The root nodules of 10 species belong to 10 genera of wild legumes were studied. Rhizobium strains were isolated and cultured in vitro. The morphologic characters were studied microscopy. The pure strains were reserved by refrigerator.