Background: Patients with chronic kidney disease are frequently suffering from the deficiency of 1,25-dihydroxyvitamin D3 (calcitriol). This study aimed to evaluate the role of vitamin D deficiency in chronic kidney disease patients, with and without dialysis and its impact on cardio vascular morbidity If fetal or not fatal. Methods: The study was carried on 100 cases and divided into three groups: Group A: 25 healthy cases (control group), Group B: 50 patients with known chronic kidney disease under conservative treatment and Group C: 25 patients with chronic kidney diseases under hemodialysis. Results: Group A (control) included 10 males and 15 females, their mean age was 42.56±3.1 years, group B (CKD) included 27 males and 23 females, their mean age was 41.6±2.5 years, group C (CKD+ dialysis) included 12 males and 13 females, their mean age was 43.3±2 years. Vitamin D was statistically higher in group A (36±7.4) than group B (17±2.5), and group C (11.4±1.5), p < 0.001. And between group B&C, p < 0.001. The group with normal ECG had statistically higher levels of vitamin D (mean= 24.5±10.8) compared to the group with abnormal ECG (mean= 13.9±4.1), p < 0.001. Eight patients of group B (16%) died during the study period, On comparison between alive and died patients regarding the clinical data; vit D was statistically higher in alive group, p=0.04. Conclusion; High prevalence of vit D deficiency in CKD patients, and showed a significant association between 25‐OH vitamin D levels and major ECG abnormalities and Echo.