The rubber tree (Hevea brasiliensis) is one of the most important domesticated crops planted commercially for the production of natural rubber (NR) worldwide. However, one of the biggest constraints of rubber cultivation is foliar diseases, which cause stunted growth of young rubber plants and reduced yield in mature rubber trees. Among the leaf diseases, Colletotrichum Leaf Disease (CLD) is one of the most common diseases causing economic loss. Two species of Colletotrichum viz. C. acutatum and C. gloeosporioides are the causative agents of Colletotrichum leaf disease. In addition to these, two other species were also isolated from infected leaf samples and included in this study. Colletotrichum spp on rubber trees ie. C. acutatum and C. gloeosporioides infect immature leaves and persist even in the mature leaves, but C. siamense and C. fructicola infect mature leaves and cause different kinds of symptoms. The present study was focused on the different Colletotrichum spp. infecting rubber trees and analysis of their phenotypic, genotypic and pathogenicity variations.