Background: The present study was conducted for evaluating the role of serum magnesium levels in chronic heart failure. Materials & methods: A total of 100 patients with chronic heart failurenormal sinus rhythm were included in the present study. Blood samples were obtained and serum magnesium levels were assessed in all the patients. On the basis of magnesium levels, all the patients were divided into two study groups; 41 patients with normal magnesium levels (>2mEq/L) and 59 patients with low magnesium levels (≤ 2 mEq/L). Profile was compared among the two study groups. All the results were recorded in Microsoft excel sheet and were analysed by SPSS software.