Abstract: Guava anthracnose was found more prevalent during the main season (April-September) than in off-season (November-February). Pestalotiopsis psidii, Colletotrichum gloeosporioides and Botryodiplodia theobromae were established as causal organisms of guava anthracnose. On potato dextrose agar medium, the growth of P. psidii was observed to be too slow as against the very quick growth of B. theobromae. All the pathogens grew well at 28 and 300C except only the P. psidii at 300C. No varieties were found resistant against all three pathogens tested but local variety I, II and IV proved resistant only against Pestalotiopsis psidii both in vitro and in situ. The Pear shaped fruits had less susceptibility than elliptical round fruits. Local varieties were less susceptible than commercial ones. In inoculated condition, variety kanchannagar showed less susceptibility in comparison with the variety sarupkati and kazipayara. Immature fruits of local variety showed decline in ascorbic acid content when diseased.