Background: Left ventricular hypertrophy (LVH) is the most common cardiovascular abnormality in children with CKD, with a reported prevalence of 17%–49%. Aim: To evaluate the role of FGF23 as early predictor of LVH in children on regular hemodialysis, aiming at reducing morbidity, mortality of these children. Methods: This was a prospective cross-sectional observational study that was conducted on 48 children on regular hemodialysis at Nephrology Unit, Pediatric Department in Zagazig University Hospitals. Results: FGF23 levels were significantly higher in the group with LVH compared to the non LVH group (mean ± SD: 752 ± 246 vs. 535 ± 208 Pg/mL, p=0.002). NT pro-BNP levels were also significantly higher in the LVH group. There was a statistically significant negative correlation between FGF23 levels and fractional shortening (r=-0.442, p=0.002), and a positive correlation between FGF23 and NT pro-BNP levels (r=0.391, p=0.006). However, no significant correlations were found between FGF23 and BMI, dialysis duration, CBC, urea, serum albumin tests or serum PTH. Positive correlation between FGF23 and patient age negative correlation between FGF23 and 25(OH)D levels. Positive correlation between FGF23 and serum creatinine. Conclusion: FGF23 has a role for early prediction of LVF in children on regular hemodialysis which helps in reducing morbidity, mortality of these children.