Guava (Pasidium guajava Linn.) belongs to the family Myrtaceae, it is an important member of this family. Guava dieback caused by Colletotrichum gloeosporioides, Surveys were conducted in different guava growing areas of Pakistan for the data documentation of different intercrops which play role in disease development. Eight different intercrops were observed in guava orchards and disease prevalence was high in those orchards were mango and citrus were cultivated as compared to other orchards, after the samples processing and identification the Colletotrichum gloeosporioides was isolated only from mango and citrus intercrops samples. The pathogenicity test was performed by following Koch’s postulates for the confirmation of pathogen and finding significant results, Colletotrichum gloeosporioides cause the successful infection on guava healthy plants but the virulence of mango isolates was high as compared to citrus isolates. After the confirmation of pathogenicity results the Colletotrichum gloeosporioides (that were isolated from guava disease samples and intercrops) were sequenced and find the significant results, these are the same isolates, which means that mango and citrus plants as intercrop in guava orchard play role in disease development that’s why disease prevalence was high in those orchards.