Objective: Thyroid hormones play an important role in homeostasis of Calcium and Phosphorous levels by their direct action on bone turnover. The importance of this study was that the thyroid hormones inter in calcium & phosphorous metabolism and it frequently disturbed in thyroid dysfunction. It is very important to monitor changes in the levels of serum calcium & phosphorous in thyroid disorder. The objective of the present study is to assess the levels of serum calcium and phosphorus in Sudanese patients with hypothyroidism in comparison with apparently healthy controls. Materials & Methods: A clinical-based descriptive study was conducted during the period from February 2012 to June 2013. Fifty patients with Hypothyroidism (25 males and 25 females) were selected as a test group compared to fifty (25 males and 25 females) apparently healthy control from the Khartoum Teaching Hospital in Khartoum state, Sudan. Blood specimens were collected from both groups and serum levels of Calcium, Phosphrous, Thyroid stimulating hormone, Thyroxin and Tri-Iodothyronine were estimated. Results : In this study the results shows a significant decrease in the mean of serum levels of Calcium in the test group compared with the control group (p >0.0001) and a significant increase in the mean of serum levels of phosphorus in the test group compared with the control group (p >0.0001). Conclusion: The serum calcium & phosphorous levels are significantly altered in hypothyroid disorders. It is important to check the levels of these minerals in hypothyroidisms patients. Treatment of the primary cause and if necessary supplementation of minerals should be done in order to prevent further bone complications.