Crown gall disease caused by Agrobacterium tumefaciens (Conn), results in significant economic losses to the stone and pome fruit trees in nurseries. In this investigation, ten isolates were isolated from soft galls of different hosts, i.e., almond, peach, apricot, pear, grapevine, rosella, rose, lupine, and pepper, on selective D1 medium. Pathogenicity, morphological, physiological, and biochemical tests proved that the 10 isolates belonged to A. tumefaciens, biovar 1: These isolates had different effects on some host plants, whereas, some hosts were highly susceptible to the pathogen, such as almond, peach, castor-bean and tomato and some hosts were less susceptible such as pepper. Also, variation among A. tumefaciens isolates was not related to their host plants, but mostly related to variation in the bacterial genome and to variation of virulence on different hosts. The RAPD­ PCR technique indicate that variation in bacterial genome refer to the variation on bands appeared whereas, it was found some bands on all isolates except one of the isolates and also one isolate (Acl from almond) has bands doesn't exist in the other isolates. Also, isolates from the same host (Pp4 & Pp5 from peach) have band on the same location but with different amount or the band was on the different location. On the other hand, A.  radiobacter isolate has a band with high amount but this band doesn't exist in some isolates and appeared in the other but with a very weak amount.