Forty four thermophilic cellulases producing bacterial isolates were isolated at 50oCfrom compost, soil and manure samples which collected from Qalubia Governorate, Egypt. Tow isolates termed C27 and C30which gave the highest results in all determinations were identified as Bacillus circulans and Cellulomonas flavigena respectively. The highest hydrolysis clear zones on CMC medium at 50oC by the two identified isolates were (1.8 cm). Fp-ase activities were 1.9 and 1.6 U/ml, CMC- ase activity were 2.1 and 2.5 U/ml by B. circulans and C. flavigena, respectively. In addition ,their ability to produce Xylanase enzymes on oat spelt agar medium at 50oC was studied.