This study was carried out to determine the nutritional value of the two species of Ziziphus tree branches in animal nutrition. To determine digestibility, each tree species branches were mixed with a ratio of 10, 20 and 30% of the basic feed (alfalfa) and were fed to 4 mature male sheep, with feces collection method. The treatments were consisted of 7 experimental diet: alfalfa, 3 diets consisted of native Ziziphus tree branches (Ziziphus spina-christi) and 3 diets consisted of Ziziphus mauritiana tree branches in a completely randomized design. The results of chemical composition of DM, OM, CP, EE, NDF, ADF, GE and tannins for Z. spina-christi were 94. 24, 90. 07, 14. 40, 2. 01, 30. 75, 17. 65 percent, 4517. 72 (cal/gr) percent and for Z. mauritiana were 94. 61, 83. 30, 14. 56, 1. 77, 33. 90, 18. 55 percent, 4447. 26 (cal/gr), and 3. 95 percent respectively. The results showed that the digestibility of DM, OM, CP, EE, NDF, ADF and GE were significantly different (P<0. 05). Among the diet treatments, 10% Z. spina-christi had the best nutrient digestibility. The digestibility of DM, OM, CP, EE, NDF, ADF and GE for 10% Z. spina-christi were 68, 59. 1, 49. 6, 76. 1, 68. 1 and 71. 7, respectively. The findings from this study demonstrated that Ziziphus tree branches foliage has the potential to improve small livestock production in the dry lands of Bushehr by alleviating nutritional constraints during the dry season.