Abstract: Mangifera indica L., the most important tropical fruit is subjected to a number of disease at all stages of its development. Practical, efficient and accurate assessment of disease intensity is a major concern of plant pathologist. At present time there is no general up-to-date precise information’s available to asses the mango diseases. This paper provides over 9 key’s for the assessment of important mango diseases. All of which have been prepared from the literature used by different researchers and author for their research work. So this publication will be an indispensable guide line for the pathologist and other related persons.