Hevea brasiliensis is the only commercial source of natural rubber in Cameroon and its production can be severely limited by diseases such as leaf blight. The disease is mostly observed in smallholder rubber fields in SOuth West Cameroon. For this study, leaf samples were collected from infected plants. The pathogen was then isolated and identified as Pestalotiopsis microspora following the cultural and morphological characterisation of colonies developed from single spore isolates. Culture media, period of incubation, temperature and pH affected the mycelial growth of P. microspora. Inoculation on detached leaflets revealed the pathogenic capacity of this fungus. Re-isolation of the pathogen from the symptoms produced confirmed Kochs postulates. Molecular sequence analysis of the internal transcribed spacer (ITS) region 1 and 2 including 5.8S rDNA (ITS-5.8S-ITS2) confirmed the morphological identification. P. microspora was therefore identified as the causative agent of the leaf blight on rubber in South West Cameroon. The effects of some fungicides were tested in vitro on mycelial growth of P. microspora. Banko plus (Chlorothalonil 550 g L-1 + Carbendazim 100 g L-1), Penncoz (Mancozeb 800 g kg-1) and Metalm 72 WP (Cuprous oxide 600 g kg-1 + Metalaxyl 120 g kg-1) tested at different concentrations revealed inhibitory activity in vitro. Among these fungicides, a marked efficiency of Chlorothalonil + Carbendazim was observed, though the inhibition of mycelial growth was more effective with Cuprous oxide + Metalaxyl at rates: 100, 75 and 50 per cent only.