Background: A difficult task is to estimate the dry weight of hemodialysis (HD) patients. Many tools are available, but not for every HD center. Several strategies have been used to derive a more standard method of assessing dry weight in hemodialysis patients. Bioimpedance spectroscopy (BIS) device has been validated against gold standard methods of volume assessment. Objective: Assessment of hemodialysis (HD) patients' dry weight and try to find the most accurate and applied method to help those patients keep in the euvolemic state. Methodology: This cross-sectional observational study was conducted on adult and pediatric hemodialysis patients at Al-Zahraa hospital, Al-Azhar University hospital during the period from august 2019 to march 2021 after verbal consents were obtained from the participants in adults' group and caregiver in the pediatric patients; clinical assessments were performed, including assessing congested neck veins. Respiratory distress, in the same line with ultrasound assessment of inferior vena cava (IVC) diameter and BIS before and after hemodialysis in the study groups. Results: In the adult population on the clinical assessment before hemodialysis, neck veins are congested in 17 (68%) out of 25 cases versus 0 (0%) in the pediatric age group; meanwhile, IVC diameter exceeds the reference range in 19 (72%), but in the pediatric age group, it does not exceed the normal reference range in all cases. Meanwhile, BIS assessment, 23 (92%) of the adult group are overhydrated versus 7 (28%) in the pediatric age group.  Conclusion: Body composition monitoring seemed to be a helpful diagnostic tool that reasonably complements existing clinical methods in assessing the dry weight of HD patients.