Objectives: This study aimed to assess serum total calcium and calcium/phosphorus ratio in patients with primary hypertension and correlate these parameters with blood pressure. Methods: This prospective comparative study included 50 newly diagnosed primary hypertension patients and 50 age- and sex-matched normotensive controls. Serum calcium was measured using arsenazo III reagent and serum phosphorus using ammonium molybdate reagent. Additional investigations included CBC, RFT, LFT and abdominal ultrasound. Results: The mean age was 44.06±11.74 years and 54% were males. Mean serum calcium (8.7±0.5 vs 9.1±0.6 mg/dL) and phosphorus (2.9±0.7 vs 3.5±0.4 mg/dL) were significantly lower, while calcium-phosphorus ratio was significantly higher (3.20±0.73 vs 2.63±0.30) in cases vs controls (p<0.05). Serum calcium negatively correlated (r=-0.391) and calcium-phosphorus ratio positively correlated (r=0.530) with blood pressure (p<0.05). Conclusion: Serum calcium and calcium-phosphorus ratio show significant alterations in primary hypertension, correlating with blood pressure severity. Monitoring and managing these parameters may be considered in hypertension management.