The comparative evaluation of different less-well researched forages will yield promising candidates to overcome the limitations of feed sources in most sub-tropic areas during drought. These resources may provide enough supply for animals' growth and milk production. Therefore, the main objective of the present study was to investigate the effect of using the viability of complete replacement of berseem hay in the diet of Barki ewes with cassava, or Acacia neloitca or Atriplex halimus leaves on ewes and their lambs' performance. For this berseem hay, “BH" in the diets of sheep was substituted with leaves of cassava, acacia or Atriplex. Forty late pregnant Barki ewes (43.2±1.1 Kg body weight) were divided into four groups in this evaluation trial. Animal groups fed either control diet (900 g concentrate feed mixture “CFM" + 600 g BH), or the tested diets, in which substituted BH with 600 g leaves of cassava, acacia, or Atriplex. Biweekly live body weight of ewes was recorded in the morning before feeding, while their lambs were weighed at the birthing then biweekly until weaning. Digestibility trials and nitrogen balance were implemented for the tested diets. Milk yield and its composition as well as blood analysis were also carried out. The economic efficiency was calculated for the experimental groups. Data of the studied parameters were statistically analyzed using the General Linear Model's procedures of SAS GLM (SAS, (2004). Cassava recorded the highest (P<0.05) values of most digestibility coefficients and feeding value parameters as well as dry matter intake and nitrogen balance. Both cassava and acacia were the best ones in maintaining the body weight and weight gain for both ewes and their lambs compared to the control and Atriplex groups. Milk yield was increased (P<0.01) in the cassava diet and milk protein, fat, ash, and solid not fat were increased (P<0.05) in the substituted forage diets compared with the control. Somatic cell count was almost similar in all tested groups. Cassava group had higher (P<0.05) serum total protein and the lowest A/G ratio, urea, and creatinine concentrations when compared to the control. Cassava increased (P<0.05) lambs weaning weights and daily weight gain compared to other treatments. It could be concluded that cassava, acacia and Atriplex are valuable alternatives to berseem hay in Barki ewe diets. Ewes fed cassava tended to have high body weight, milk yield and their lamb's daily gain compared with that fed acacia or Atriplex.