Aim This study aims to evaluate the calcifying effect of phosphorus on vascular smooth muscle by detecting the association between serum phosphorus and valvular and vascular calcification. Patients and methods The study included 40 patients who were diagnosed to have end-stage renal disease within the last 5 years with their age ranging from 18 to 40 years. The patients were divided into two groups according to the duration of dialysis: group I included patients on regular hemodialysis for less than 1 year and group II included patients on regular hemodialysis for 1–5 years duration. All patients were subjected to full history taking and clinical examination: laboratory investigations (urea, creatinine, parathyroid hormone (PTH), calcium, phosphorus, liver function test, sodium, potassium level), measurement of coronary artery calcification by multi-slice computed tomography (MSCT) coronary calcium scoring, vavular calcification by echocardiography, and carotid intima media thickness by gray scale ultrasound. Results Coronary calcium score, valvular calcification, and carotid intima media thickness had insignificant correlation with age, duration of dialysis, serum calcium, and parathormone hormone; however, all of them had positive moderate significant correlation with serum phosphorous level. Conclusion Hyperphosphatemia has an effective role in the progression of valvular and vascular calcification; so, good control of hyperphosphatemia may participate in preventing and delaying the progress of cardiovascular calcification and subsequently decrease cardiovascular morbidity and mortality in end-stage renal disease.