Sugarcane (cv. C 9) cultivated in three governorates of upper Egypt (El- Menia, Assiut, Quena) were sampled to assess the occurrence and characteristic of the endophytic G. diazotrophicus isolated from tissues of plants, as well as to determine its abundance in tissues and rhizosphere soil. The 14 endophytic isolates obtained from tissues (roots and stem buds) showed phenotypic and biochemical characteristics identical to those internationally reported in Bergey's Manual of Systemic Bacteriology (2005). No variation were recorded in cell morphology of isolates, or colony characteristic and pigmentation, or physiological traits due to area of plantation or to N - fertilization scheme practiced. The N₂ - fixing activity of the isolated strains ranged from 12.2:17.6 mg N/ g sucrose consumed from culture media (LGI). The enumeration, by the MPN technique on LGI semisolid medium, for the endophytic cells in tissues of sugarcane grown in Assiut Exptl. Farm of faculty of agriculture, recorded mean numbers of 2.0 – 15.4 × 10⁵/ g tissues, whereas mean estimated rhizosphere cells ranged from 2.6 – 16 × 10⁴/ g of rhizosphere soil.