During the last few years a new disease symptoms appeared and spread  on mango trees in Ismailia Governorate from which Ganoderma sp. was frequently isolated. The disease starts as rot  in the basal area of mango trees, followed by the growth of distinctive structures known as "brackets" and finally plant death. Three isolates is of Ganoderma sp. were isolated for the frist time from naturally infected mango trees in three locations at Abo-Swear district  El-Karakrah , Abo-Kharwae and El-Wasfia) , Ismailia Governorate , Egypt . Microscopic examination of isolated pure cultures showed hyphal system trimitic(generative hyphae , skeletal hyphae and binding hyphae),basidiospores and chlyamidospores.) of Ganoderma sp. Pathogenicity test on mango transplants , with  isolated Ganoderma sp.,  under greenhouse conditions revealed that Ganoderma sp.  was pathogenic and it caused sudden wilt root rot and dieback causing wilt to inoculated mango transplants. In the same time, results indicate that the artificially inoculated discs of different other fruit and wood trees (Host range) in their susceptibility to the pathogen under study based on the external rotted discs of tested woody plants. Mango and kaki exhibited 100% of rotted discs two week after inoculation. On the contrary, no fungal growth was observed on inoculated guava and olive discs under the same conditions. In the meantime, plum, casuarina and berry showed 77.8, 62.0 and 56.8 % infection in inoculated discs, respectively .Starch and mannose used as carbon source recorded a noticeable increase in the linear growth of Ganoderma sp. study followed by sucrose in Ganoderma growth medium, maltose and manitol. The tested fungus gave maximum growth rate on Yeast extract 10 days after incubation at   25 ^oC followed by Molt extract, Peptone and Ammonium sulphate which found to be best source of nitrogen for this fungus. The optimum temperature for the linear growth of Ganoderma sp. ranged from 20 to 30 ^oC. T. harzianium recorded the highest percentage of inhibition against Ganoderma sp.  followed by T. virens. However, Chaetomium globosum showed the lower percentage of inhibition.